Blueberries: What the Cognition and Heart Trials Actually Show

The woman ahead of me in the frozen aisle was holding her phone up to the freezer door, matching the bag in her hand to the bag in a video. The clip, one of thousands circulating this spring, promises that a daily cup of blueberries “reverses memory loss” and “works like a blood pressure pill.” She bought three bags. I understood the impulse completely.

As of March 2026, searches for blueberries benefits have surged again, pushed less by any new discovery than by old trial results recut into thirty-second claims. The underlying research is genuinely interesting. A handful of randomized trials, a few very large observational cohorts and one disappointing three-year diet study together tell a story that is more careful, and in some ways more useful, than the video version.

So here is that story, trial by trial, with the strength of each finding spelled out. Where the science is thin, I will say so. Where it is solid, I will say that too.

Why blueberries benefits are trending right now

Every few years a food gets its moment, and in 2026 it is the blueberry’s turn once more. The current wave started with wellness accounts stitching together three real findings: a 2012 Harvard analysis linking berries to slower cognitive aging, a 2019 British trial showing better blood vessel function after six months of daily blueberries, and small brain imaging studies in older adults. Compressed into one breathless caption, they become “blueberries reverse memory loss.”

The trouble is not that the studies are fake. It is that compression strips out the parts that matter: who was studied, for how long, what actually improved and what did not budge. A trial that improved one memory test in 26 retirees over 12 weeks is a useful signal. It is not a treatment for dementia, and the researchers who ran it never said it was.

Two other forces feed the trend. Frozen wild blueberries have become a staple of “brain food” meal-prep content, and the broader interest in food as medicine has turned every antioxidant into a headline. Antioxidants are compounds that help neutralize unstable molecules called free radicals, which can damage cells. Blueberries are rich in a particular class called anthocyanins, the pigments that make the skin dark blue. Anthocyanins are plausible biological actors; they are not magic.

My own view, after reading the trials rather than the captions, is that blueberries earn a place in a sensible diet on the strength of modest but repeatable findings, especially for blood vessels. The brain story is promising and unfinished. Keeping those two verdicts separate is the whole point of this piece.

What changed recently

Nothing dramatic has changed in the laboratory. What has shifted is the way existing results are being read, so it helps to date them properly.

In April 2012, researchers using the Nurses’ Health Study published an analysis in Annals of Neurology of 16,010 women aged 70 and older. Those eating the most blueberries and strawberries showed cognitive decline that lagged behind low-berry eaters by what the authors estimated as up to 2.5 years. That is observational data: it shows association, not cause.

In January 2013, Circulation carried a report from the same cohort’s younger arm, following 93,600 women for 18 years. Those with the highest intake of anthocyanin-rich foods, mostly blueberries and strawberries, had a 32 percent lower rate of heart attack than those with the lowest, after adjusting for other lifestyle factors. Again, observational.

In May 2019, the American Journal of Clinical Nutrition published the strongest randomized trial so far: 115 adults with metabolic syndrome ate the equivalent of one cup, half a cup or zero blueberries daily for six months. The one-cup group improved endothelial function, the ability of blood vessel linings to relax, and raised HDL (“good”) cholesterol. Blood pressure and insulin resistance did not change. The half-cup group showed no benefit.

In July 2023, the New England Journal of Medicine reported the three-year MIND diet trial, which includes berries as a core food. Cognitive scores improved in both the MIND group and the control group, with no meaningful difference between them. That result tempers the “brain food” story considerably.

As of March 2026, those four studies remain the load-bearing evidence. The viral clips are recirculating them, not reporting anything new.

What is actually in a cup of blueberries?

A cup of fresh blueberries, about 150 grams, delivers roughly 85 calories, 21 grams of carbohydrate, about 15 grams of natural sugar and 3.6 grams of fiber. It supplies about a quarter of a day’s vitamin C, roughly a third of vitamin K, and a meaningful amount of manganese, a mineral involved in bone formation and metabolism.

Those numbers put blueberries in the middle of the fruit pack. Raspberries carry twice the fiber. Oranges carry more vitamin C. Where blueberries stand out is in polyphenols, a large family of plant compounds, and specifically in anthocyanins. Cultivated blueberries contain on the order of 100 to 160 milligrams of anthocyanins per 100 grams, among the highest of common fruits, and the lowbush “wild” type can roughly double that.

Why does that matter? In laboratory and animal studies, anthocyanins reduce inflammation, improve nitric oxide signaling (the chemical message that tells blood vessels to relax) and appear to influence the gut microbiome, the community of bacteria in the intestine that affects everything from immunity to metabolism. Blood levels of anthocyanins after eating berries are low, so researchers suspect the breakdown products made by gut bacteria do much of the work.

The fiber is not a footnote. Soluble fiber slows sugar absorption and feeds those same gut bacteria, and the whole-fruit package, with its water and bulk, fills you up for very few calories. That is one reason the trials keep using whole or freeze-dried fruit rather than isolated extracts.

One more detail worth knowing: the pigment lives in the skin. Smaller berries have more skin per gram, which is part of the wild-versus-cultivated difference discussed later.

Blueberries for memory: what the cognition trials found

The cognitive trials are the part of the story most distorted online, so the details deserve space.

The earliest human trial, in 2010, gave wild blueberry juice daily for 12 weeks to nine older adults with early memory complaints. They improved on a word-pairing memory test compared with their own baseline. Nine people, no placebo for the main group, 12 weeks. A pilot, nothing more.

In 2017, a British team gave 26 healthy adults aged 65 to 77 either blueberry concentrate or a placebo drink for 12 weeks. Brain imaging showed increased blood flow in regions involved in attention and memory, and the blueberry group improved on one working-memory task. Other tests showed no difference.

A 2018 American trial randomized 37 adults aged 60 to 75 to freeze-dried blueberry powder or placebo for 90 days. The blueberry group made fewer errors on a task-switching test, a measure of mental flexibility. Most other measures, including standard memory recall, did not differ.

A 2022 trial in middle-aged adults with insulin resistance and mild memory concerns reported better performance on some attention tasks after 12 weeks of wild blueberry powder. Insulin resistance is a state in which cells respond poorly to insulin, raising blood sugar; it is itself a risk factor for cognitive decline.

Notice the pattern. Each trial is small, runs three months or less, and finds a benefit on one or two tests among many. None measured dementia, and none lasted long enough to. Mild cognitive impairment, the clinical label for memory changes beyond normal aging but short of dementia, was not reversed in any of them; a slightly better test score is a different thing.

Honest summary: blueberries for memory is a credible hypothesis with early, inconsistent human support. That is a reason for larger trials, not for a promise.

Are blueberries good for your heart? The vessel and cholesterol trials

Here the evidence is firmer, and the 2019 metabolic syndrome trial is the anchor. Metabolic syndrome is a cluster of risk factors, including a large waist, high blood pressure, high triglycerides, low HDL and raised blood sugar, that together increase heart disease risk.

After six months, the one-cup group showed an improvement in flow-mediated dilation, a measure of how much an artery in the arm widens when blood flow increases, of about 1.5 percentage points. That sounds small, but across populations a one-point improvement in this measure has been associated with meaningfully lower cardiovascular event rates. Arterial stiffness also improved, and HDL cholesterol rose modestly. LDL, blood pressure and insulin sensitivity were unchanged.

Earlier, shorter trials pointed the same way. An eight-week study in adults with metabolic syndrome reported lower blood pressure and reduced arterial stiffness with daily blueberry powder, but it had 48 participants. Trials in healthy younger adults have shown improvements in vessel function within hours of eating blueberries, fading by the next day. That short-lived effect is why the trials emphasize daily, sustained intake.

Blood pressure deserves its own sentence, because the videos lean on it hardest. Pooled analyses of berry trials find reductions of a few millimeters of mercury in some studies and none in others; the largest and longest trial found no change. The fair reading is “possibly a small effect, not reliably shown.” A fruit is not a substitute for a prescribed blood pressure medicine, and no trial suggests otherwise.

On the observational side, the 93,600-woman cohort found that eating blueberries and strawberries three or more times a week was associated with a 32 percent lower risk of heart attack. Whether the berries or the broader habits of berry-eaters explain that gap cannot be settled by that study design.

So, are blueberries good for your heart? The vessel-lining data say yes, modestly, over months. The hard-outcome data say probably, with caveats.

Blueberries and blood sugar: do they help or hurt?

People living with diabetes often ask whether a fruit this sweet belongs on their plate. The answer, from both trial data and dietary guidance, is yes in sensible portions.

Blueberries have a glycemic index of roughly 53, placing them in the low range. The glycemic index ranks how quickly a food raises blood sugar compared with pure glucose at 100. Fiber and the fruit’s water content slow the rise, and a cup contains less sugar than a medium banana.

Observational research from the Harvard cohorts has linked higher intake of whole fruit, with blueberries among the strongest associations, to a lower risk of developing type 2 diabetes, while fruit juice intake trended the other way. That contrast is a useful reminder that form matters: the same sugar arrives differently when the fiber has been removed.

Randomized trials of blueberries on insulin sensitivity are mixed. A small six-week study in adults with obesity and insulin resistance found improved insulin sensitivity with a daily blueberry smoothie. The six-month metabolic syndrome trial found no change. Short-term trials in healthy adults sometimes show a smaller post-meal glucose spike when berries are eaten with starchy food, an effect attributed to polyphenols slowing carbohydrate digestion.

Practically, that means blueberries pair well with a meal rather than being eaten as a sugar hit on their own, and that dried blueberries, which concentrate sugar and often carry added sugar, behave differently from fresh or frozen. People who monitor glucose can simply check their own response; individual variation is real.

None of this changes a diabetes plan on its own. Anyone adjusting carbohydrate targets or medication timing around fruit should do so with the clinician or dietitian managing their care.

What the evidence actually says, graded by strength

Medicine ranks evidence roughly in this order: randomized controlled trials, where people are assigned by chance to a food or a placebo, sit at the top because they can show cause and effect; observational studies, which track what people choose to eat, sit below because other habits travel with the food; expert opinion and laboratory work sit lower still. Applying that ladder to blueberries:

Blood vessel function and HDL cholesterol: moderate evidence. One well-run six-month randomized trial plus several shorter ones point the same direction. The effect is modest and appeared at one cup a day, not half.

Heart attack and stroke: low to moderate, observational only. Large cohorts show associations; no randomized trial has measured these outcomes, and none is likely to, given the decades it would take.

Blood pressure: low. Small, inconsistent trial effects; the largest trial found none.

Cognitive test performance: low. Several tiny randomized trials, each positive on a minority of tests, with different tests improving in different studies. Real signal or chance? Larger trials are needed to tell.

Slower cognitive aging: low to moderate, observational. One large, carefully adjusted cohort analysis. Plausible, unproven.

Dementia prevention: no direct evidence. The one long randomized diet trial that included berries, the MIND study, found no advantage over the control diet at three years.

Type 2 diabetes risk: low to moderate, observational. Consistent cohort associations for whole fruit; mixed trial data on insulin sensitivity.

Cancer, eye health, weight loss: largely laboratory and animal data, with sparse human trials. Not graded here because there is too little to grade.

If you remember one line, make it this: the heart findings are the ones a cautious clinician would call real, and the brain findings are the ones a cautious clinician would call interesting.

Blueberry trials at a glance: a comparison table

Numbers travel badly through social media, so here are the key human studies side by side. Watch the participant counts and durations; they say more about the strength of each result than the headline finding does.

Study (year)	Design	People and duration	Main finding
Wild blueberry juice (2010)	Pilot, no control arm for main group	9 older adults, 12 weeks	Better word-pair memory vs baseline
Nurses’ Health Study berries (2012)	Observational cohort	16,010 women 70+, 6 years of testing	Highest berry intake linked to slower cognitive decline
Nurses’ Health Study II anthocyanins (2013)	Observational cohort	93,600 women, 18 years	32% lower heart attack rate at highest intake
Blueberry concentrate (2017)	Randomized, placebo-controlled	26 adults 65–77, 12 weeks	Increased brain blood flow; one memory task improved
Freeze-dried powder (2018)	Randomized, placebo-controlled	37 adults 60–75, 90 days	Fewer task-switching errors; recall unchanged
Metabolic syndrome trial (2019)	Randomized, placebo-controlled	115 adults, 6 months	Better vessel function and HDL at 1 cup/day; blood pressure unchanged
MIND diet trial (2023)	Randomized diet comparison	604 adults 65+, 3 years	No cognitive difference vs control diet

Three things jump out. The cognitive trials together enrolled fewer people than the single heart trial. The only study long enough to speak to real-world cognitive aging, the MIND trial, was negative, although it tested a whole diet rather than blueberries alone and its control group also ate well. And the heart result appeared at a full cup daily while the half-cup arm showed nothing, which argues for consistency over the occasional handful.

A fair critic would add that most trials used freeze-dried powder standardized to a known anthocyanin content, which real-world eaters cannot replicate exactly. That does not undermine the findings; it means the fresh-fruit equivalent is an estimate.

Wild blueberries vs regular: does the type matter?

“Wild” on a freezer bag does not mean foraged. It refers to lowbush blueberries, a smaller species that grows on low shrubs in cold regions and is commercially harvested from managed fields. The familiar plump supermarket berry is the highbush species, bred for size and shelf life.

The nutritional difference is mostly about skin. Because lowbush berries are tiny, a cup contains far more individual berries and therefore more pigment-rich skin per gram. Laboratory analyses generally find roughly twice the anthocyanin concentration in wild compared with cultivated fruit, along with slightly more fiber and a more intense flavor. Several of the cognition trials used wild blueberry powder for exactly this reason.

Does that translate into a bigger health effect? No trial has directly compared the two types head to head over months, so the honest answer is “probably somewhat, unproven.” The six-month heart trial used cultivated highbush berries and still found benefit, which argues that regular blueberries are not a lesser choice.

The practical implication is reassuring. Buy the type you will actually eat. Frozen wild berries keep for months and are easy to portion into breakfast; fresh highbush berries are easier to snack on and travel better in a lunchbox. Either way the anthocyanins are in the fruit, not in a label.

One caution about the word “organic”: pesticide residue is a reasonable concern for some shoppers, but there is no evidence that organic blueberries deliver more of the compounds studied in the trials. Rinsing berries under running water just before eating removes most surface residue on conventional fruit, and rinsing just before rather than long before keeps them from turning soft.

Fresh, frozen, dried, powder or juice: which form keeps the benefits?

The trials used almost every form, which is convenient because it lets us compare.

Frozen berries hold up remarkably well. Anthocyanins are stable at freezer temperatures, and because commercial berries are frozen within hours of harvest, frozen fruit can match or exceed fresh fruit that has spent a week in transit and a refrigerator. Ice crystals rupture the skin, which may make pigments slightly more available. For year-round daily eating, frozen is the pragmatic choice.

Freeze-dried powder is what most trials actually fed people, typically an amount standardized to one or two cups of fresh fruit. It is a research tool more than a kitchen staple. Powders sold to consumers vary enormously in anthocyanin content and are not tested as medicines are; treat them as food, not as a supplement with a guaranteed content.

Dried blueberries concentrate sugar by removing water, and many brands add sugar or oil. They are fine in small amounts, but a quarter cup of dried fruit carries the sugar of a full cup of fresh berries with less of the filling bulk.

Juice removes fiber and most of the skin, where the pigment sits. The 2010 pilot used juice and found a signal, but later trials moved to whole-fruit powder for a reason. Juice also behaves like a sugary drink in blood sugar terms.

Cooking matters less than people fear. Baking does reduce anthocyanins, with losses in some studies around 10 to 20 percent for muffins, and more for long simmering. Blueberries folded into oatmeal or yogurt lose almost nothing.

The ranking, then: whole fresh or frozen first, lightly cooked whole fruit second, powder as a reasonable alternative, dried fruit sparingly, juice last.

How many blueberries a day is realistic?

The trial with the clearest benefit used one cup a day, about 150 grams fresh, and found no benefit at half a cup. That is the most defensible number we have, and it is also the serving size the American Heart Association uses for berries.

It is a lot of blueberries. A cup every single day is a commitment many people abandon within weeks, which is why I would rather see a realistic half-cup habit than an ambitious cup that lasts a fortnight. The NHS counts an 80-gram portion, roughly a generous handful, as one of your five a day. Hit that most days and you are already in the range where the observational studies saw associations with heart and brain outcomes.

Three ways to make it stick, drawn from how trial participants managed: stir frozen berries into a breakfast you already eat so the habit is anchored; keep a bag in the freezer rather than relying on fresh fruit that spoils; and rotate in strawberries, blackberries or raspberries, since the observational data were about berries broadly, not blueberries alone.

Can you eat too many? For healthy adults the main consequence of two or three cups a day is a lot of fiber arriving at once, with the bloating that implies, plus around 250 calories you may not have budgeted for. There is no established toxic dose of a fruit. People on blood thinners and people managing carbohydrate intake have specific reasons to keep portions steady, covered below.

The deeper point is that a cup of blueberries displacing a pastry does more than a cup added on top of one. The trials fed berries within ordinary diets; the biggest real-world gain often comes from what the fruit replaces.

Common myths about blueberries benefits, corrected

“Blueberries reverse memory loss.” No trial has shown this. Small studies found better scores on one or two cognitive tests after 12 weeks in people with mild memory complaints. Those are measurements, not recoveries, and the one three-year diet trial found no cognitive advantage.

“They work like a blood pressure pill.” The longest, largest randomized trial found no change in blood pressure. Some small trials found drops of a few points; others found none. Prescribed medicines lower blood pressure by amounts measured in tens of thousands of patients. Fruit has not been, and should never replace them.

“Blueberries are the number one antioxidant food.” Rankings based on laboratory antioxidant capacity were so widely misused that the United States Department of Agriculture withdrew its database in 2012. Test-tube antioxidant scores do not predict what happens in the body, a point MedlinePlus makes in its overview of antioxidant research.

“Frozen blueberries lose their nutrients.” The opposite is closer to the truth; freezing preserves anthocyanins well, and most trials used frozen or freeze-dried fruit.

“People with diabetes should avoid them.” Whole blueberries have a low glycemic index and are associated with lower diabetes risk in cohort studies. Portion and form matter; the fruit itself is not off limits.

“A blueberry supplement does the same thing.” Capsules and powders vary widely, are not regulated as medicines, and have not been tested in the long trials that whole fruit has. The gut bacteria that seem to activate anthocyanins also need the fiber that capsules leave out.

“You need the wild ones.” Wild berries carry more pigment per gram, but the best heart trial used ordinary cultivated fruit.

Each myth contains a grain of fact, which is exactly why it spreads. The correction is not that blueberries are useless; it is that they are a good food, not a therapy.

Who should take extra care: medicines, allergies and digestion

Blueberries are about as safe as a food gets, but a few groups benefit from a moment’s thought.

People taking warfarin, a blood thinner whose effect is influenced by vitamin K intake, are usually advised to keep vitamin K consumption consistent from week to week rather than to avoid it. A cup of blueberries supplies roughly a third of the daily vitamin K reference value, so suddenly starting or stopping a daily cup could nudge clotting tests. The practical step is to tell the clinician or anticoagulation clinic about the change so monitoring can account for it. Newer anticoagulants are not affected by vitamin K in the same way, but mentioning dietary changes still makes sense.

People with diabetes who adjust medication to carbohydrate intake should count a cup of blueberries as what it is, about 21 grams of carbohydrate. Any change to a medication plan belongs to the prescribing clinician.

True blueberry allergy is uncommon but documented, with reactions ranging from itching in the mouth to, rarely, hives and swelling. Some people with birch pollen allergy notice oral tingling with raw fruit, a condition called oral allergy syndrome that typically settles when the fruit is cooked.

Blueberries contain small amounts of salicylates, compounds related to aspirin. People with a diagnosed salicylate sensitivity sometimes react; this is rare and usually already known to the individual.

Digestive effects are the most common complaint. A large quantity eaten quickly, especially on a low-fiber baseline diet, can cause gas, bloating or loose stools. Building up over a week or two avoids most of it. Blue-tinged stools after a big serving are harmless pigment and startle more people than they should.

Pregnant and breastfeeding people can eat blueberries freely as part of a varied diet; there is no evidence of harm, and the folate and fiber are welcome.

When to see a doctor

Blueberries themselves almost never send anyone to a clinic. The reasons to seek care are about the conditions people hope blueberries will fix, and about recognizing when a food question has become a medical one.

Seek urgent care, by emergency services if needed, for any of the following after eating blueberries or any food: swelling of the lips, tongue or throat; difficulty breathing or wheezing; widespread hives; faintness or a racing heart. These are signs of a serious allergic reaction and need treatment, not observation.

Book a prompt appointment if you notice memory changes that interfere with daily life: getting lost on familiar routes, repeating questions within minutes, difficulty managing money or medicines, or family members expressing concern. These warrant a clinical assessment, which may include blood tests, a medication review and cognitive testing. Treatable contributors such as thyroid problems, vitamin B12 deficiency, depression, sleep apnea and medication side effects are common, and no amount of fruit addresses them. Starting blueberries instead of booking that appointment is the one genuinely harmful thing this trend could encourage.

See a clinician about heart risk if you have been told your blood pressure or cholesterol is high and have no follow-up plan, or if you experience chest pressure, unexplained breathlessness, palpitations or ankle swelling. Call emergency services for chest pain lasting more than a few minutes, especially with sweating, nausea or pain spreading to the arm or jaw.

Talk to the prescribing clinician before changing fruit intake meaningfully if you take warfarin or a medicine whose dose is matched to your carbohydrate intake, and before taking any product marketed as blueberry extract alongside prescription medicines.

Finally, see a doctor if digestive symptoms attributed to berries persist beyond two weeks, include blood, or come with weight loss. Those are not berry symptoms.

Every decision about medicines, including whether a dietary change permits any adjustment, rests with the clinician who knows your history.

Frequently asked questions

Do blueberries really improve memory?

Only modestly, and only on certain tests in small, short trials. Studies of 9 to 37 older adults over 12 weeks found better scores on one or two cognitive tasks, not across the board. A large observational study linked berry eating to slower cognitive aging, but no trial has shown blueberries prevent memory loss or dementia.

How many blueberries a day for heart health?

The trial with the clearest benefit used one cup, about 150 grams, every day for six months; half a cup showed no effect. A cup is also the American Heart Association serving size for berries. If a daily cup is unrealistic, a steady handful most days still fits the range seen in observational studies.

Are frozen blueberries as healthy as fresh?

Yes. Anthocyanins are stable when frozen, and commercially frozen berries are processed within hours of harvest, so they can match or beat fresh berries that have traveled for a week. Most of the clinical trials used frozen or freeze-dried fruit. Thaw them into oatmeal or yogurt and very little is lost.

Wild blueberries vs regular: which is better?

Wild lowbush blueberries carry roughly twice the anthocyanin per gram because they have more skin relative to flesh. No long trial has compared the two directly, and the best heart trial used ordinary cultivated berries and still found benefit. Choose whichever you will eat consistently; consistency matters more than species.

Can people with diabetes eat blueberries?

Yes, in sensible portions. Whole blueberries have a low glycemic index of about 53 and roughly 21 grams of carbohydrate per cup, and cohort studies link whole fruit to lower type 2 diabetes risk. Dried berries and juice behave differently. Any change to carbohydrate targets or medication should be made with the treating clinician.

Do blueberries lower blood pressure?

Not reliably. Some small trials found reductions of a few millimeters of mercury; the largest six-month trial found no change at all. The evidence grade is low. Blueberries are a reasonable part of a blood-pressure-friendly eating pattern, but they are not a substitute for prescribed medicine, which should never be changed without the prescriber.

Is a blueberry supplement as good as eating the fruit?

Probably not. Capsules and powders vary widely in anthocyanin content, are regulated as foods rather than medicines, and have not been tested in the six-month trials that whole fruit has. They also omit the fiber that feeds the gut bacteria thought to activate anthocyanins. Whole or frozen fruit remains the evidence-based form.

Can blueberries interact with blood thinners?

A cup supplies about a third of the daily vitamin K reference value, which can influence warfarin. The usual advice is to keep vitamin K intake consistent rather than avoid it, and to tell your clinician or anticoagulation clinic before starting or stopping a daily cup so monitoring can adjust. Never change the medicine yourself.

Why are blueberries good for your heart?

Anthocyanins appear to improve nitric oxide signaling, helping blood vessel linings relax, and the fiber supports cholesterol and blood sugar control. In a six-month randomized trial, one cup a day improved flow-mediated dilation by about 1.5 percentage points and raised HDL cholesterol. Observational data link regular berry eating with fewer heart attacks.

Can eating too many blueberries be harmful?

For most healthy adults, no beyond digestive discomfort. Two or three cups a day delivers a lot of fiber quickly, which can cause bloating or loose stools, plus around 250 calories. Blue-tinged stools are harmless pigment. People on warfarin or carbohydrate-matched diabetes medicines should keep portions steady and discuss changes with their clinician.

References

• MedlinePlus: Antioxidants
• NHS: 5 A Day portion sizes

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.