The Machine Doesn't Change the Fruit. It Changes What Your Body Does With It.

What you'll learn

What pasteurization actually is, and why "cold-pressed" and "never heated" are not the same claim

Why juice counts as free sugar while whole fruit does not

Why blood glucose cannot settle whether a smoothie is "the same as" whole fruit

What the peer-reviewed comparisons of juicer types actually found

Which juice has real evidence behind it, and how narrow that evidence is

How SmartBar applies the deficiency framework

SmartBar assesses products using three things we can verify: ingredient composition, level of processing, and nutritional data. We use two organizing terms throughout our education. Deficiency means something the body needs and isn't getting. Toxicity means a burden the body must process and clear, not a poison.

Both machines can raise your intake of plants. Both can also make a large quantity of plants easy to consume very quickly. Juicing does that by separating liquid from pulp; blending does it by turning the whole plant into something drinkable. What matters is rarely what the machine does to one apple. It is how many apples, carrots or handfuls of spinach end up in the glass.

Start here: what the two machines actually do

A juicer separates. It pulls liquid out of the plant and leaves dry pulp behind. Out comes water, sugars, minerals, vitamins and some of the plant's phytochemicals. What stays in the pulp is most of the fibre.

A blender separates nothing. It breaks the whole thing into smaller pieces, so the fibre is still in the glass, disrupted rather than removed.

One product distinction matters throughout this page. Studies of 100% fruit juice are not studies of fruit drinks, juice cocktails or beverages containing added sugars or only a proportion of juice. Research that pools the two produces different answers from research that separates them, and that turns out to matter a great deal further down.

What pasteurization is, in plain language

Pasteurization is heating a liquid to a set temperature for a set time, long enough to destroy the organisms that make people ill. It is not sterilization: it kills pathogens and most spoilage organisms, not everything.

The familiar numbers come from milk, where batch treatment holds the liquid around 63°C (145°F) for at least 30 minutes and the common modern method holds it at least 72°C (161°F) for 15 seconds before rapid cooling. Hotter, shorter variants produce ultra-pasteurized and shelf-stable cartons.[1]

But juice is not regulated by a temperature. In the United States the requirement is a performance standard: a process capable of reducing the pertinent pathogen by at least five logs, a hundred-thousand-fold. The pertinent pathogen is whichever organism of public health significance is most resistant to the treatment being used and likely to occur in that juice, which is Salmonella for orange juice and either E. coli O157:H7 or Cryptosporidium parvum for apple juice.[2]

Asked whether the milk conditions suffice for juice, FDA answers that it depends: the time and temperature vary with the product, process, target organism and acidity, and while the milk conditions usually work, each processor must validate them for their own juice.[2] The milk figures are a starting point, not a definition.

The juice safety rule also does not require heat at all. FDA wrote it so the kill step could be something other than pasteurization, which is the space high pressure processing occupies: the juice is sealed in its container and subjected to around 600 MPa, roughly 87,000 psi, for a few minutes, disabling microorganisms without cooking anything.[3]

Which produces the label confusion worth clearing up. Cold-pressed describes how juice was extracted. Pressure processing describes how it was preserved. Cold-pressed juice sold refrigerated on a shelf may subsequently have been pressure-processed, so a bottle promising "cold-pressed, never heated" can still be a processed product, processed by pressure rather than temperature. And the two are not interchangeable: the European Food Safety Authority concluded pressure processing cannot achieve reductions equivalent to thermal pasteurisation of milk under the applicable legal requirements, though combinations can be identified that meet the recommended performance criteria.[3]

Free sugars, and where two definitions draw the line differently

The sugar in fruit is a mix of fructose, glucose and sucrose in proportions that vary by fruit. The term that matters is different.

The World Health Organization defines free sugars as sugars added by a manufacturer, cook or consumer, plus the sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates, and recommends keeping them under 10% of energy, with a conditional suggestion of under 5%. The guideline explicitly does not cover sugars in fresh fruit and vegetables or in milk, because no adverse effects from those have been reported.[4]

So juice is free sugar even when nothing was added. Nothing was put in; something was taken out.

The blender exposes a boundary WHO does not explicitly draw. It names juice and concentrate, but does not say what to do with whole fruit whose cellular structure has been mechanically disrupted without anything being removed.

The United Kingdom does draw that line. Following advice from its Scientific Advisory Committee on Nutrition, the UK definition treats sugars in fruit and vegetables that have been blended, pulped, puréed, extruded or powdered as free sugars, on the grounds that the cellular structure has been broken down, while sugars in dried, canned, stewed and pressed fruit stay outside it because the structure survives. Smoothies are therefore counted as free sugars in the UK and are not addressed by the WHO definition at all.[15]

That is a classification decision, not proof that a smoothie behaves like juice inside a person. As the experiments below show, keeping the fibre while breaking the structure produces effects that differ from both intact fruit and fibre-free juice.

Free sugar is an oral-health category too. Juice combines fermentable sugar with acidity, which makes the concern plausible. The human evidence is less tidy than the warning: a systematic review found that prospective cohort studies in children and adolescents showed no association between 100% juice and erosion, and either no association or an inverse association with caries, while short-term trials in adults using enamel specimens showed softening and demineralisation.[5] That review concluded the evidence is inconclusive and attributed the trial findings to conditions unlike normal drinking. Worth knowing when weighing that interpretation: the review was partly funded by a juice industry trade association, and two authors received funding or fees from it.[5]

The glucose curve is not the whole meal

Here is the popular claim: blending shreds the fibre, so a smoothie hits your blood sugar like juice. Somebody tested it, and the result went the other way.

Twenty healthy young adults ate gala apple with the seeds removed plus blackberries, whole or blended. Peak glucose and glucose incremental area under the curve were significantly lower after the blended fruit, p < 0.05.[6] The authors proposed that grinding the blackberry seeds released fibre and other components that chewing leaves locked inside, and they caution against extrapolating to commercial smoothies.

But blood glucose is one outcome, and an old experiment showed why that matters.

In 1977, ten subjects ate meals matched at 60 g of available carbohydrate as whole apples, apple purée, or fibre-free juice. Juice could be consumed eleven times faster than whole apples and purée four times faster. With the rate of eating equalised, satiety ranked whole apple above purée above juice. Plasma glucose rose to similar levels after all three. But there was a striking rebound fall after juice and a lesser one after purée, absent after whole apples, and insulin rose higher after both processed forms than after the intact fruit.[7]

Same glucose peak. Different insulin. Different satiety. Different rebound.

Modern imaging has since shown part of the mechanism. In a randomized crossover experiment, whole apple took substantially longer to empty from the stomach than either purée or juice, about 65 minutes against 41 and 38, and produced greater fullness and satiety than juice.[8] And in a meal study, eating whole apple before lunch reduced total energy intake at that meal relative to control, while applesauce and juice did not reproduce the effect, and adding fibre back to juice did not either.[9]

So blending is not juicing. But blending is not chewing either.

The fibre stays. The structure does not. Depending on the fruit and the outcome measured, breaking that structure can change nutrient accessibility, how fast you consume it, how long it stays in your stomach, satiety, glucose or insulin, and those do not all move in the same direction. Which is exactly why a single glucose curve cannot tell you whether a smoothie is "the same as" whole fruit.

Whole fruit against juice, and how unsettled it is

Three long-running cohorts followed 187,382 US health professionals across 3,464,641 person-years, during which 12,198 developed type 2 diabetes. Per three servings a week, with individual fruits mutually adjusted, blueberries came in at 0.74, apples and pears 0.93, oranges 0.99, cantaloupe 1.10. Fruit juice, at the same increment, 1.08, 95% CI 1.05 to 1.11.[10]

That cohort found a difference. It does not settle the question, and the later evidence is less alarming.

A meta-analysis of 14 prospective cohorts searched to August 2024 found no significant association between fruit juice overall and type 2 diabetes, RR 1.06, 95% CI 0.98 to 1.15. Split by product, non-100% juice carried the risk and 100% juice did not.[11] An independent analysis a decade earlier found the same split: sugar-sweetened fruit juice 1.28, 95% CI 1.04 to 1.59, against 100% fruit juice 1.03, 95% CI 0.91 to 1.18.[12]

And a counterweight, so this does not overcorrect. A dose-response meta-analysis found that sugar consumed as a beverage, including fruit juice, was associated with diabetes risk while total sugar, sucrose, fructose and added sugar were not.[13]

So: whole fruit has the stronger evidence and the intact structure. Juice is not equivalent to it. But "not equivalent to whole fruit" is a much smaller claim than "juice causes diabetes," and the pooled evidence does not support making that second claim confidently.

One detail from the original cohort survives all of this and is worth keeping: the associations of individual fruits were not determined by their glycemic index or load.[10] Whatever separates these foods, the cohort data suggest it is not simply how fast the sugar arrives.

The machines, and the confident numbers that come with them

Search for a juicer and you will meet precise figures. 2.7 times more vitamin C. 82% against 67% at 24 hours. 89% against 54% for "enzyme activity." Many trace back to companies selling juicers or to affiliate sites, attributed to journals by name and year with no title, no authors and no identifier you could check.

Here is what the peer-reviewed work found.

In a direct comparison, five juices common in Thai markets were prepared with a centrifugal juicer, a cold-press juicer and a blender, then measured for ascorbic acid, total phenolics, total carotenoids and two antioxidant assays. There were no significant differences between cold-pressed and centrifugal juice on any measure. The authors write that their findings strongly question the superiority claim and that it could be misleading. They also tested the shelf-life claim: refrigerated cold-pressed juice held to about day five then declined, and at room temperature degraded within 48 hours.[14]

In that comparison, the proposed nutritional superiority of cold pressing did not appear. That does not establish that extraction method never matters: effects can differ by produce, by processing conditions and by which compound is measured, and other work has reported differences in both directions.

What it does show is how far the confident figures can run ahead of the evidence — quoted to the decimal point by people selling the machine, from a literature that has not settled the question.

And the most repeated claim is the weakest. Slow juicers are marketed on preserving enzymes. "Preserves enzymes" is not the same as "improves health." Even if one method leaves more of a particular plant enzyme active in the glass, that does not establish that it survives digestion in a meaningful amount, is absorbed, or changes any human outcome. We found no clinical evidence supporting the health claim the marketing rests on.

Fresh at home against a bottle from the shelf

Processing changes things, modestly and unevenly. In orange juice over 36 days of refrigeration, there was no significant difference in total phenolics at day zero between thermal and pressure processing, carotenoids fell after both, and heat reduced flavonoids and anthocyanins while pressure increased them. Over storage both declined, but pressure-treated juice did not differ significantly from fresh until day 22, while heat-treated juice sat below fresh throughout.[16]

Heat is not automatically the villain: in passion fruit purée, thermal pasteurization preserved antioxidants as effectively as pressure processing, differing only in aroma.[17] And the effect can depend heavily on the fruit: vitamin C was undetectable in watermelon juice after ten minutes of pasteurization while mango lost 27%.[18] Fresh juice is not stable either, degrading at room temperature within 48 hours.[14]

So the trade is not fresh nutrients against dead bottled juice. Fresh preparation minimises storage time and gives you control over ingredients. Validated commercial processing reduces microbial risk and extends shelf life. Both processing and storage alter individual nutrients, and the size and direction of those changes depend heavily on the fruit, the compound and the treatment. Fresh does not mean sterile, and commercial does not mean empty.

What the evidence actually supports

One of the clearest juice-specific randomized literatures belongs to a vegetable.

A 2024 meta-analysis restricted to adults meeting the clinical threshold for hypertension pooled eleven trials and 349 patients. Nitrate-rich beetroot juice reduced clinical systolic blood pressure by 5.31 mmHg, 95% CI −7.46 to −3.16, at 200 to 800 mg of nitrate a day, with no sign of tolerance.[19]

The qualifications are all in the paper. No significant effect on clinical diastolic pressure or on any 24-hour ambulatory measure, high heterogeneity, and certainty graded low, with the authors urging caution.[19] A clinic reading that moves while the all-day reading does not is a meaningful gap.

And nitrate may not explain the whole effect. A separate meta-analysis of 22 trials found patterns suggesting a possible nitrate-independent component and pointed to other beetroot compounds as candidates, without establishing the mechanism.[20]

That is what good evidence looks like here: one juice, one group, one measure, low certainty, unsettled mechanism. Not a general case for juicing.

If you take medication for blood pressure, this belongs with your prescriber rather than a website. The research itself frames the question as whether this could be an adjunct to drug treatment, which is a clinical decision. Nothing here is a reason to start, stop or change any medication.

Detox is the claim. Concentration is the documented risk.

Start with the word on the bottle. There is no established evidence that a juice cleanse removes accumulated toxins from a healthy body. A 2015 review found no compelling research supporting detox diets for weight management or toxin elimination; a 2017 review found that juicing and detox diets can produce short-term weight loss through very low calorie intake, followed by regain when normal eating resumes; and there have been no studies of the long-term effects of these programmes at all.[21] The underlying critical review reports that no randomised controlled trials of commercial detox diets in humans have been conducted.[22] US regulators have taken action against companies in this category for hidden ingredients, false disease claims and unapproved device marketing.[21]

Something does happen during a cleanse. Less food goes in, weight can move. What has not been demonstrated is the commercial claim itself: that drinking juice for a period meaningfully increases elimination of vaguely defined toxins, or produces a benefit that way.

The better-documented biology runs the other way: concentrating plants concentrates compounds as well as nutrients.

Oxalate is found in many plants, especially leafy greens, and is cleared by the kidneys. There are published, biopsy-confirmed cases of what a concentrated load can do. A 65-year-old woman on a ten-day cleanse, with a prior gastric bypass and recent prolonged antibiotics, developed acute kidney injury that progressed to end-stage renal disease.[23] A 68-year-old man on a spinach-heavy daily juice diet for six months reached a calculated oxalate intake of about 1,500 mg a day, roughly ten times a typical diet, with biopsy showing extensive tubular oxalate deposits in otherwise healthy tissue.[24] Further cases appear in the clinical literature.[25]

Three things must be said about them. These are case reports: they establish that it happens and how, not how often. The detailed cases above involved important predisposing factors, including prior bypass surgery, recent antibiotics and volume depletion, and other published cases involve diabetes or existing kidney vulnerability. And the first report is titled a "green smoothie cleanse" while its abstract describes the preparation as juicing greens and fruits, so it cannot settle a blender-versus-juicer question either way.[23] The relevant exposure is the concentrated oxalate load, not which machine produced it.

Raw juice also carries a microbiological risk that is unevenly disclosed. FDA says most juice sold in the United States is pasteurized or otherwise treated, but untreated juice remains available. It has caused outbreaks of E. coli O157:H7, Salmonella and Cryptosporidium, and packaged untreated juice must carry a warning naming children, older adults and people with weakened immune systems.[26] But that requirement covers juice packaged for consumption elsewhere. Retail sellers of juice for consumption on-site, explicitly including restaurants and juice bars, are exempt.[26] The absence of a warning at a juice counter is a regulatory boundary, not a safety signal. FDA also records outbreaks linked to smoothies made with unpasteurized juice.[27]

Children, and one interaction worth knowing

A 2024 systematic review pooled 42 studies, including 17 cohorts covering 45,851 children with a median age of 8. Each additional daily serving of 100% fruit juice was associated with a 0.03 higher change in BMI, 95% CI 0.01 to 0.05, and in subgroup analysis the association was larger in children under 11 and absent in older ones. In adults the cohort association reversed once total energy was accounted for, and randomized trials showed no effect.[28] There were no randomized trials in children at all.

Paediatric guidance is more conservative than adult marketing. The American Academy of Pediatrics states that fruit juice offers no nutritional benefit over whole fruit for infants and children, has no essential role in a healthy balanced diet, and should not be introduced before 12 months absent a clinical reason; it strongly discourages unpasteurized juice.[29] Notably, AAP itself describes the 100%-juice-and-obesity literature as uncertain, and recommends removing juice from the diets of children with excessive weight gain rather than from all children.[29] Amounts for a particular child belong with a paediatrician, not with us.

One interaction genuinely worth knowing. Compounds in grapefruit irreversibly inactivate an enzyme in the small intestine that governs how much of certain oral medicines reaches your bloodstream. One whole grapefruit or 200 mL (about 7 fl oz) of juice is enough to matter, all forms do it including the whole fruit, and because the inactivation is irreversible, spacing the juice away from the dose does not help. Seville oranges, limes and pomelos share the effect; navel and valencia oranges do not. It is documented or predicted for many medicines and is drug-specific rather than a class effect, which is exactly why we name none of them: no reader could work out from a category whether their own medicine is affected. If you take regular oral medication, ask your pharmacist or prescriber.[30]

Key takeaways

A juicer removes fibre. A blender keeps it and breaks the structure. Neither transformation can be judged from sugar content or fibre grams alone.

Blending is not juicing, but blending is not chewing either. Whole fruit is more satiating than purée and purée more than juice, and processed forms raised insulin more than intact fruit even when glucose peaks matched.

Juice counts as free sugar even with nothing added. WHO does not explicitly classify blended whole fruit; the UK does, counting its sugars as free sugars once the cellular structure has been broken down.

The whole-fruit versus juice evidence is more unsettled than either side says. Later pooled analyses found no significant diabetes association for 100% juice, while juice drinks carried risk.

A direct comparison of juicer types found no significant difference, while many of the confident figures online trace back to sellers.

One of the clearest juice-specific benefits studied is narrow: beetroot juice lowered clinic systolic pressure in people with hypertension, on low-certainty evidence, with no effect on 24-hour measures.

Detox has no supporting trials. Concentrated oxalate exposure has caused documented kidney injury in susceptible people, in published juice and "green smoothie cleanse" cases.

How to think about this in thirty seconds

Ask whether the fibre left the glass, or stayed and got smaller. That is the difference between the two machines, though not the whole story.
Ask what else changed: how fast you can drink it, how long it stays in your stomach, how full it leaves you.
Check whether a study is about 100% juice or a juice drink. The answers differ.
Ask whether a claim is about what is in the glass or what happens in a person. Most are the first, sold as the second.
Remember that making plants easy to drink can change the dose as well as the structure. Concentration matters, and so do microbial safety, medication interactions and who is drinking it.

What SmartBar does with this

Juice is where our three questions visibly pull against each other. A bottle of 100% juice has a clean ingredient list. It has also had part of the food removed, separating its sugars from much of the fibre and structure that surrounded them, which is a processing question rather than an ingredient one. Our framework exists to notice exactly that gap, which is the point our nutrition article makes about food structure.

We sell no juicers, blenders or juice, and we score no appliances. That is worth saying here, because in this field almost every confident source has something in the checkout: the juicer sellers, the blender marketing, the pressure-processing brands, and even the trade association that part-funded the only systematic review of juice and dental health. Four different products, one recurring pattern.

What we will not do is give you a verdict. The evidence says juice is not whole fruit, that blending is not juicing and not chewing either, that the machine matters less than many of the claims made for it, and that some of the clearest harms come not from sugar spikes but from concentration, contamination and specific interactions. What you do with a blender on a Tuesday morning is yours to decide.

This article is educational and is not medical advice. Nothing here is a reason to start, stop or change any medication. If you take regular oral medication, ask your pharmacist or prescriber before making grapefruit or grapefruit juice a habit. If you have kidney disease, a history of kidney stones, have had bariatric surgery, or are pregnant, immunocompromised, elderly or caring for a young child, the safety questions on this page apply to you differently and belong with a qualified clinician who knows your history.

Keep exploring: Nutrition · Hydration · Front-of-package claims · Obesity · Longevity

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References

Pasteurization methods for milk. International Dairy Foods Association, "Pasteurization," summarising the time and temperature combinations of the FDA Grade "A" Pasteurized Milk Ordinance. https://www.idfa.org/pasteurization (Vat pasteurization holds the liquid at least 30 minutes; High Temperature Short Time raises milk to at least 161°F/72°C for not less than 15 seconds with rapid cooling and is the most common US method; Ultra Pasteurized requires not less than 280°F/138°C for two seconds; aseptic processing, or Ultra High Temperature, uses commercially sterile equipment and aseptic filling for a shelf-stable product. Cited as illustration of the familiar milk methods, not as a definition of juice pasteurization — see reference 2.)
US Food and Drug Administration, juice HACCP regulation (21 CFR Part 120) with "Guidance for Industry: Juice HAACP Hazards and Controls Guidance, First Edition" and "Questions and Answers on Juice HACCP Regulation." (The requirement is a 5-log reduction — a hundred-thousand-fold — in the pertinent microorganism, defined as the most resistant organism of public health significance likely to occur in that juice. Salmonella species for orange juice; E. coli O157:H7 or Cryptosporidium parvum for apple juice, depending on which is more resistant to the treatment used. FDA states that pasteurization times and temperatures to achieve a 5-log reduction vary with product type, process, target microorganism and pH, and that while milk conditions of 161°F for 15 seconds will in most cases achieve it for juice, the processor must validate this for their own product. The kill step is not required to be pasteurization, a choice FDA made explicitly to allow other technologies. Citrus processors may apply surface treatment of the fruit toward the requirement; all other juices must be treated after extraction.)
High pressure processing. European Food Safety Authority Panel on Biological Hazards, "The efficacy and safety of high-pressure processing of food," PMCID: PMC8902661. (Pressure without heat, industrially on the order of 600 MPa or approximately 87,000 psi for a few minutes. EFSA concluded that HPP cannot achieve log reductions equivalent to those from thermal pasteurisation of milk under the applicable legal requirements, while target pressure and holding-time combinations can be identified that achieve the 5 to 8 log reductions recommended as pasteurisation performance criteria.)
World Health Organization (2015). Guideline: Sugars Intake for Adults and Children. Free full text: NCBI Bookshelf NBK285525 and NBK285523. (Free sugars defined as monosaccharides and disaccharides added by manufacturer, cook or consumer, plus sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates. Strong recommendation to reduce to under 10% of total energy, conditional suggestion under 5%. Explicitly does not apply to sugars in fresh fruit and vegetables or in milk. The definition names juices and concentrates and does not address mechanically disrupted whole fruit; the article states this gap rather than filling it.)
Liska, D., Kelley, M., Mah, E. (2019). "100% Fruit Juice and Dental Health: A Systematic Review of the Literature." Frontiers in Public Health 7:190. PMCID: PMC6640211. (Eight publications from five prospective cohorts, all in children or adolescents, and nine RCTs, all in adults. Cohorts found no association with erosion and no or inverse association with caries; adult trials found decreased microhardness, increased enamel loss and increased demineralisation of enamel specimens. Authors conclude the evidence is not conclusive and attribute the trial results to small, short-term designs using intra-oral devices without normal plaque and saliva action, under conditions unlike normal consumption. Competing interests: two authors received partial funding from the Juice Products Association to conduct the review and a third received a consulting fee from the same association. Disclosed in the body because the review's interpretation favours the funder's interest and it is the only synthesis of this literature available.)
Crummett, L.T., Grosso, R.J. (2022). "Postprandial Glycemic Response to Whole Fruit versus Blended Fruit in Healthy, Young Adults." Nutrients 14(21):4565. DOI: 10.3390/nu14214565. PMID: 36364827. PMCID: PMC9657402. (20 healthy college students; gala apple with seeds removed plus blackberries, whole against blended. Glucose maximum and incremental area under the curve significantly lower after blended fruit, p < 0.05. Authors hypothesise release of fibre and other components from ground blackberry seeds and caution against extrapolating to commercial smoothies. Small single-meal study in healthy young adults.)
Haber, G.B., Heaton, K.W., Murphy, D., Burroughs, L.F. (1977). "Depletion and disruption of dietary fibre: effects on satiety, plasma-glucose, and serum-insulin." The Lancet 2(8040):679–682. DOI: 10.1016/s0140-6736(77)90494-9. PMID: 71495. (Ten subjects, test meals matched at 60 g available carbohydrate as whole apples, purée, or fibre-free juice. Juice consumed eleven times faster than apples and four times faster than purée. With ingestion rate equalised, satiety ranked apples above purée above juice. Plasma glucose rose to similar levels after all three, but a striking rebound fall followed juice and a lesser one purée, absent after apples; serum insulin rose higher after juice and purée than after apples.)
Krishnasamy, S., Lomer, M.C.E., Marciani, L., Hoad, C.L., Pritchard, S.E., Paul, J., Gowland, P.A., Spiller, R.C. (2020). "Processing Apples to Puree or Juice Speeds Gastric Emptying and Reduces Postprandial Intestinal Volumes and Satiety in Healthy Adults." The Journal of Nutrition 150(11):2890–2899. DOI: 10.1093/jn/nxaa191. PMID: 32805050. (Open-label randomized controlled three-way crossover, 18 healthy adults, isocaloric 178 kcal portions of whole apple, apple purée and apple juice, with MRI measurement. Gastric emptying half-time approximately 65 minutes for whole apple against 41 for purée and 38 for juice; purée and juice did not differ significantly from each other. Whole apple produced significantly greater fullness and satiety than juice.)
Flood-Obbagy, J.E., Rolls, B.J. (2009). "The effect of fruit in different forms on energy intake and satiety at a meal." Appetite 52(2):416–422. DOI: 10.1016/j.appet.2008.12.001. PMID: 19110020. PMCID: PMC2664987. (58 adults, matched apple preloads. Whole apple eaten before a meal reduced energy intake at that meal relative to control, an effect not reproduced by applesauce, juice, or juice with fibre added back.)
Muraki, I., Imamura, F., Manson, J.E., Hu, F.B., Willett, W.C., van Dam, R.M., Sun, Q. (2013). "Fruit consumption and risk of type 2 diabetes: results from three prospective longitudinal cohort studies." BMJ 347:f5001. PMID: 23990623. PMCID: PMC4073481. (187,382 participants across three cohorts; 3,464,641 person-years; 12,198 incident cases. Fruit juice 1.08, 95% CI 1.05 to 1.11 per three servings/week; total whole fruit 0.98. The associations of individual fruits were not determined by their glycemic index or glycemic load. Observational, food-frequency based, in US health professionals.)
Lee, C-w., Myung, S-K. (2025). "Consumption of Fruit Juice and Risk of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Prospective Cohort Studies." The American Journal of Medicine. (14 prospective cohorts from 1,591 screened articles, searched to 3 August 2024. Overall fruit juice RR 1.06, 95% CI 0.98 to 1.15, not significant. Non-100% fruit juice was associated with increased risk; 100% fruit juice was not.)
Xi, B., et al. (2014). "Intake of Fruit Juice and Incidence of Type 2 Diabetes: A Systematic Review and Meta-Analysis." PLOS One 9(3):e93471. PMCID: PMC3969361. (Four studies and 191,686 participants for sugar-sweetened fruit juice, four studies and 137,663 for 100% juice. Sugar-sweetened fruit juice RR 1.28, 95% CI 1.04 to 1.59; 100% fruit juice RR 1.03, 95% CI 0.91 to 1.18, not significant. An independent replication of the same split a decade before reference 11.)
Della Corte, K.A., Bosler, T., McClure, C., Buyken, A.E., LeCheminant, J.D., Schwingshackl, L., Della Corte, D. (2025). "Dietary Sugar Intake and Incident Type 2 Diabetes Risk: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies." Advances in Nutrition 16(5):100413. DOI: 10.1016/j.advnut.2025.100413. PMID: 40122386. PMCID: PMC12145082. PROSPERO CRD42023401800. (29 cohorts overall, with 14 fruit-juice cohorts totalling 490,413 participants; each additional serving of fruit juice associated with RR 1.05, moderate-certainty evidence. Sugar consumed as a beverage, including fruit juice, was associated with incident type 2 diabetes, while total sugar, sucrose, fructose and added sugar showed null or inverse associations. Cited as a counterweight so the correction in the body does not overshoot.)
Khaksar, G., Assatarakul, K., Sirikantaramas, S. (2019). "Effect of cold-pressed and normal centrifugal juicing on quality attributes of fresh juices: do cold-pressed juices harbor a superior nutritional quality and antioxidant capacity?" Heliyon 5(6):e01917. DOI: 10.1016/j.heliyon.2019.e01917. PMID: 31286079. PMCID: PMC6587058. Chulalongkorn University. Open access. (Five juices, three extraction methods. No significant differences between cold-pressed and centrifugal in ascorbic acid, total phenolics, total carotenoids, FRAP or DPPH. Authors state the superiority claim is strongly questioned and could be misleading. Cold-pressed juice under home refrigeration unchanged to day 5, declining from day 6; at room temperature, declining within 48 hours.)
Swan, G.E., Powell, N.A., Knowles, B.L., Bush, M.T., Levy, L.B. (2018). "A definition of free sugars for the UK." Public Health Nutrition 21(9):1636–1638. DOI: 10.1017/S136898001800085X. PMID: 29587886. PMCID: PMC5962881. (The UK operational definition, built on SACN's 2015 Carbohydrates and Health report plus further SACN advice to Public Health England in 2016. SACN advised that sugars naturally present in fruit and vegetables that have been blended, pulped, puréed, extruded or powdered be treated as free sugars, on the basis that the cellular structure has been broken down, while sugars in dried, canned, stewed and pressed fruit and vegetables fall outside the definition because the structure is intact. The definition covers all added sugars in any form, all sugars naturally present in fruit and vegetable juices, purées and pastes and similar products whose structure has been broken down, and all sugars in drinks other than dairy-based ones. SACN recommended free sugars not exceed 5% of total dietary energy from age 2. Note on a common error: the arbitrary 50% attribution for dried, canned and stewed fruit belonged to the superseded non-milk extrinsic sugars system, not to free sugars; an earlier draft of this article repeated that conflation and it was removed.)
Vieira, F.N., Lourenço, S., Fidalgo, L.G., Santos, S.A.O., Silvestre, A.J.D., Jerónimo, E., Saraiva, J.A. (2018). "Long-Term Effect on Bioactive Components and Antioxidant Activity of Thermal and High-Pressure Pasteurization of Orange Juice." Molecules 23(10):2706. DOI: 10.3390/molecules23102706. PMID: 30347848. PMCID: PMC6222786. (36 days refrigerated. No significant difference in total phenolics at day 0; carotenoids decreased after both; thermal decreased flavonoids and anthocyanins while HPP increased flavonoids. HPP juice differed significantly from fresh only after 22 days; thermally treated juice was below fresh throughout.)
Niu, H., et al. (2022). "Comparison of the Effects of High Pressure Processing, Pasteurization and High Temperature Short Time on the Physicochemical Attributes, Nutritional Quality, Aroma Profile and Sensory Characteristics of Passion Fruit Purée." Foods 11(5):632. DOI: 10.3390/foods11050632. PMCID: PMC8909329. (HPP 600 MPa/87,000 psi for 5 minutes, pasteurization 85°C/185°F for 30 seconds, HTST 110°C/230°F for 8.6 seconds. Thermal pasteurization preserved antioxidants and antioxidant capacity as effectively as HPP; the difference appeared in aroma.)
Mandha, J., Shumoy, H., Matemu, A.O., Raes, K. (2023). "Characterization of fruit juices and effect of pasteurization and storage conditions on their microbial, physicochemical, and nutritional quality." Food Bioscience 51:102335. DOI: 10.1016/j.fbio.2022.102335. (Volume 51 is dated February 2023; the 2022 element of the DOI reflects online processing, not the publication year. Thermal pasteurization at 80 ± 2°C with varying holding times across different fruits. Vitamin C undetectable in watermelon juice after 10 minutes of pasteurization against a 27% reduction in mango juice. Treatment effects are fruit-dependent.)
Grönroos, R., Eggertsen, R., Bernhardsson, S., Praetorius Björk, M. (2024). "Effects of beetroot juice on blood pressure in hypertension according to European Society of Hypertension Guidelines: A systematic review and meta-analysis." Nutrition, Metabolism and Cardiovascular Diseases 34(10):2240–2256. DOI: 10.1016/j.numecd.2024.06.009. PMID: 39069465. (Eleven trials, 349 patients with clinical BP ≥140/≥90. Clinical systolic BP mean difference −5.31 mmHg, 95% CI −7.46 to −3.16, I² = 64%. No significant effect on clinical diastolic BP or 24-hour BP. 200–800 mg nitrate daily, no tolerance observed. Certainty graded low; authors state results should be interpreted with caution. No competing interests declared.)
Bahadoran, Z., Mirmiran, P., Kabir, A., et al. (2017). "The Nitrate-Independent Blood Pressure–Lowering Effect of Beetroot Juice: A Systematic Review and Meta-Analysis." Advances in Nutrition 8:830–838. DOI: 10.3945/an.117.016717. PMID: 29141968. PMCID: PMC5683004. (22 randomized trials, 650 intervention and 598 control participants. Systolic −3.55 mmHg, diastolic −1.32 mmHg. Reports patterns suggesting a possible nitrate-independent component and identifies other beetroot compounds as candidates; does not establish the mechanism.)
National Center for Complementary and Integrative Health, "Detoxes and Cleanses: What You Need To Know." https://www.nccih.nih.gov/health/detoxes-and-cleanses-what-you-need-to-know (A 2015 review found no compelling research supporting detox diets for weight management or toxin elimination; a 2017 review found juicing and detox diets can cause initial weight loss from low calorie intake with weight gain on resuming a normal diet; no studies exist on long-term effects of detoxification programmes. Records that FDA and FTC have taken action against several companies selling detox or cleansing products for hidden ingredients posing significant health risk, false claims of treating serious disease, and marketing colon-cleansing devices for unapproved uses.)
Klein, A.V., Kiat, H. (2015). "Detox diets for toxin elimination and weight management: a critical review of the evidence." Journal of Human Nutrition and Dietetics 28(6):675–686. DOI: 10.1111/jhn.12286. PMID: 25522674. (No randomised controlled trials have been conducted to assess the effectiveness of commercial detox diets in humans. The handful of clinical studies claiming enhanced detoxification are described as hampered by flawed methodologies and small sample sizes.)
Makkapati, S., D'Agati, V.D., Balsam, L. (2018). "'Green Smoothie Cleanse' Causing Acute Oxalate Nephropathy." American Journal of Kidney Diseases 71(2):281–286. (65-year-old woman, normal baseline kidney function, 10-day oxalate-rich green cleanse; predisposing factors a remote gastric bypass and recent prolonged antibiotics; biopsy showed abundant polarizable calcium oxalate crystals in the epithelium and lumen of renal tubules; progressed to end-stage renal disease. Note on characterisation: the report is titled a "green smoothie cleanse" while its abstract describes the preparation as juicing oxalate-rich green leafy vegetables and fruits. It should not be used to infer a blender-versus-juicer distinction, and an earlier draft of this article did exactly that on the strength of the title. Authors declare no relevant financial interests. Case report.)
Chaudhari, et al. (2022). "Acute Oxalate Nephropathy Caused by Excessive Vegetable Juicing and Concomitant Volume Depletion." Case Reports in Nephrology. DOI: 10.1155/2022/4349673. (68-year-old man, six months of spinach-heavy daily juice; calculated oxalate intake approximately 1,500 mg/day, about ten times a typical diet; biopsy showed extensive tubular oxalate deposits with tissue relatively free of chronic change; progressed to end-stage renal disease. Case report.)
Getting, J.E., Gregoire, J.R., Phul, A., Kasten, M.J. (2013). "Oxalate nephropathy due to 'juicing': case report and review." The American Journal of Medicine 126(9):768–772. DOI: 10.1016/j.amjmed.2013.03.019. (See also Raja, N., Radhakrishnan, H., Masilamani, S. (2023), Cureus, DOI 10.7759/cureus.51226.)
US Food and Drug Administration, "What You Need to Know About Juice Safety," with the juice HACCP regulation and labelling rule. https://www.fda.gov/food/buy-store-serve-safe-food/what-you-need-know-about-juice-safety (FDA states that most juice sold in the United States is pasteurized, and that juice may also be treated by non-heat processes. Outbreaks involving E. coli O157:H7, Salmonella species and Cryptosporidium parvum. Packaged untreated juice must bear a warning identifying children, the elderly and persons with weakened immune systems. The labelling requirement applies to processors packaging untreated juice for consumption off-site; retail sellers of juice for consumption on-site, such as restaurants and juice bars, are exempt.)
US Food and Drug Administration, "Fruits, Veggies and Juices — Food Safety for Moms-to-Be." (Records foodborne illness outbreaks associated with smoothies made with unpasteurized juice.)
Nguyen, M., Jarvis, S.E., Chiavaroli, L., et al. (2024). "Consumption of 100% Fruit Juice and Body Weight in Children and Adults: A Systematic Review and Meta-Analysis." JAMA Pediatrics 178(3):237–246. PMID: 38227336. (42 studies: 17 in children, all prospective cohorts and no randomized trials, 45,851 children, median age 8; 25 in adults, 268,095. Children: 0.03 higher BMI change per additional daily serving, 95% CI 0.01 to 0.05, 0.15 in those under 11 against approximately zero in older children. Adult cohort association reversed after adjustment for total energy; pooled randomized trials showed no significant association. Authors note 100% juice supplies vitamins, antioxidants and polyphenols. The under-11 finding is a subgroup analysis and the paediatric evidence carries substantial heterogeneity.)
Heyman, M.B., Abrams, S.A.; AAP Section on Gastroenterology, Hepatology, and Nutrition and Committee on Nutrition (2017). "Fruit Juice in Infants, Children, and Adolescents: Current Recommendations." Pediatrics 139(6):e20170967. (Fruit juice offers no nutritional benefit over whole fruit for infants and children and has no essential role in a healthy balanced diet; not to be introduced before 12 months absent a strong clinical basis; unpasteurized juice strongly discouraged; fruit juice distinguished from fruit drinks; grapefruit juice to be avoided with certain medications. The statement also describes the literature on 100% juice and obesity as uncertain, with recent studies failing to identify a clear connection especially above age 6, and recommends eliminating juice for children with excessive weight gain rather than for all children. Age-banded volume recommendations in the statement are deliberately not reproduced here, per editorial policy on protocols.)
Bailey, D.G., Dresser, G., Arnold, J.M.O. (2013). "Grapefruit–medication interactions: forbidden fruit or avoidable consequences?" CMAJ 185(4):309–316. DOI: 10.1503/cmaj.120951. (Furanocoumarins metabolized by intestinal CYP3A4 into reactive intermediates that bond covalently to the active site, causing irreversible mechanism-based inactivation until new enzyme is synthesised. One whole grapefruit or 200 mL of juice is sufficient to cause a clinically relevant increase in systemic drug concentration. All forms produce the effect; intravenous drugs unaffected. Seville oranges, limes and pomelos share it; navel and valencia oranges do not. Drug-specific, not a class effect; documented or predicted for more than 85 medicines.)

Sourcing note: this article cites randomized controlled trials, systematic reviews and meta-analyses, prospective cohort studies, imaging and feeding experiments, food-science comparisons, regulatory guidance and clinical case reports, with DOI/PMID where available. Study designs, sample sizes, funding and limitations are stated in the reference notes rather than left implicit, and where the literature disagrees with itself the body says so rather than picking a side. Industry funding is disclosed in the body where it bears on how a finding should be read. Case reports are labelled as case reports. This article names no juicer, blender or juice brand, ranks no products, and makes no recommendation, by editorial policy. Medications are discussed without naming any drug or drug class, because the interaction described is drug-specific rather than class-based and a category label would mislead in both directions. All measurements are given in both metric and imperial. Cross-link targets (#) resolve once the site structure is live. Reading time is measured, not asserted: body words excluding the reference list and the metadata header, counted at 225 words per minute and rounded to the nearest minute.

PRODUCTION NOTE — DELETE BEFORE PUBLICATION

Every reference was verified against an openly accessible source before the claim resting on it was written. Citation integrity audited: every marker resolves, every reference is cited, no duplicates.

Identifiers adopted from the final review without independent re-retrieval: the DOI, PMID and PMCID strings added to references 9, 14, 16, 17, 18 and 20, and the corrected volume and article number for reference 18. The substance of each of those papers was verified independently during research; only the identifier strings came from review. Confirm them at production, as we do with any supplied citation.

Three corrections are recorded inside the references rather than silently applied, because this article got each one wrong first: the arbitrary 50% attribution in reference 15, which belongs to the superseded non-milk extrinsic sugars system; the machine characterisation in reference 23, where an earlier draft inferred a blended cleanse from the paper's title while its abstract describes juicing; and the obsolete pasteurization prevalence figure removed from reference 26 and the body.

One production sequencing note. A removed reference vacated slot 15, which now holds the UK free-sugars definition, so reference numbers do not run in order of first appearance. A single manual renumbering pass happens at production alongside cross-link insertion, per our standing rule that renumbering is done once, by hand, and never by pattern replacement.

Outstanding: clinical review; production cross-links and the single manual renumbering pass.