Superfoods Without the Marketing: What's Actually in Them

Introduction

The word "superfood" has no scientific definition and no regulator that approves it. It is simply what people call foods credited with everything at once: disease protection, rejuvenation, "detox", weight loss and "immunity". The Harvard School of Public Health states plainly that the term has no scientifically grounded or regulated definition.

I don't want to write yet another "it's all a scam" article. That would be untrue: most of these foods do have real nutritional value. The problem is something else. They are sold in tiny servings, at the price of a good steak per kilogram, with promises far broader than the evidence. So from here on I'll keep three things apart: what is in the food, how much of it a person actually eats, and what has been shown in humans.

Where the Word Came From

The history of the term is usually traced back to the First World War. According to the Harvard School, the word was born as a food-marketing device, not in laboratories: United Fruit Company promoted bananas as cheap, nutritious and easily digestible food and issued brochures about their nutritional value. Later, medical journals carried "banana diets" for celiac disease and diabetes — before it became clear that celiac disease is caused by gluten. The company happily rode that wave. The exact starting year varies between sources (1917 turns up), so I won't give a specific date.

After that, fashions came in waves. One of the most telling episodes is ORAC, an "antioxidant capacity" index invented in 1991 by researchers at the National Institute on Aging and the USDA. In the ORAC table, blueberries and other berries looked like champions, and this was used in advertising for years. In 2012 the USDA took its ORAC database off its website: the agency stated that laboratory values of antioxidant capacity cannot be carried over to effects in the human body, and that they were routinely used incorrectly in advertising and in choosing foods. Some scientists (including one of the method's developers) disputed this, but the story itself shows well that "lots of antioxidants in a test tube" and "good for you" are different claims.

In the European Union, the word "superfood" is not directly banned either. The regulation on health claims (in force since 2007) requires that such wording be accompanied by an authorized, substantiated claim. I have only seen retellings of this rule in the trade press, so read the wording with caution.

How the Scheme Works

Superfood marketing almost always follows the same script:

1. An interesting substance is found in the food: a polyphenol, a carotenoid, omega-3, a mineral.
2. Its action is shown in a test tube or in mice.
3. The result is quietly transferred to the whole food.
4. A possible small effect is turned into a promise of a cure, weight loss or detox.
5. A small package is sold at a big markup.

A separate classic trick is the half-truth. Seeds really do contain omega-3, but it is plant-based ALA, not the EPA and DHA found in fish. A powder really does contain vitamins, but in a three-gram serving their contribution is negligible.

What They Promise and What It Means

The Serving Matters More Than "Per 100 Grams"

The simplest and most useful check. If 100 g of powder contains 1,000 mg of a substance, and you put 3 g into a smoothie, you get 1,000 × 3 / 100 = 30 mg. A label with per-100 g figures looks impressive, but people usually eat 2–5 g of powder, 10–30 g of seeds and a couple of grams of seaweed.

An example with chia: according to the USDA (I looked at a mirror of its database), 100 g of dry seeds contain about 34 g of fiber and about 16.5 g of protein. That is impressive until you remember that a spoonful (about 15 g) gives roughly 5 g of fiber and 2.5 g of protein. That's decent, but comparable to a slice of whole-grain bread, not a "replacement for vegetables".

A simple formula for yourself: look at the amount of the substance in your serving, multiply by how plausible the effect is, and divide by the price. If any one of the numbers looks like zero, the rest doesn't matter.

Price per Nutrient: How to Calculate It Yourself

I don't give exact prices here: they depend heavily on the country, the season and the store. The method is simple. Take the price of the package and divide by grams to get the price per gram of the product. Then multiply by how many grams you need to get the same "benefit".

• Protein: 4 g of protein from a tablespoon of spirulina (about 7 g of powder) versus 4 g of protein from half an egg. Eggs, cottage cheese and lentils almost always win on price by an order of magnitude.
• Fiber: 5 g of fiber is a spoonful of chia, but also a couple of slices of whole-grain bread or half a cup of cooked beans.
• Omega-3: ALA is found in flax and walnuts for pennies, while EPA and DHA are found in fatty fish. A "super seed" powder adds nothing here.

Check your receipt the way you check your mobile plan: price per unit, not pretty packaging.

What Is What: Food, Powder, Extract

These are different products, and data cannot be carried over between them:

• whole food;
• dried food;
• powder;
• standardized extract;
• capsules with a concentrate.

A pinch of turmeric in soup and a capsule of bioavailable curcumin differ like a cup of tea and a caffeine tablet. Extracts can have a stronger effect, but the risk of interactions and side effects is higher too. Ordinary food is considerably gentler in this respect; supplements require caution, especially when taking medication and with liver and kidney disease.

Cinnamon: A Good Example of Substitution

Under the word "cinnamon", mostly cassia is sold. Ceylon cinnamon (Cinnamomum verum) exists, costs more and contains far less coumarin.

Sticks can be told apart: Ceylon is thin, multilayered like a rolled-up leaf, light in color and breaks easily; cassia is thick, hard, dark, reddish and smells sharper. In ground form you can't tell them apart by sight: you need labeling and a reliable producer.

What About the Benefit

Cinnamon contains aromatic compounds and polyphenols. But a 2012 Cochrane review (10 randomized trials, 577 participants, mostly with type 2 diabetes, usually about 2 g of cassia a day) found no statistically significant effect on HbA1c and postprandial glucose, and the results for fasting glucose were inconclusive; the authors concluded that there are insufficient data to recommend cinnamon for diabetes. New studies may have appeared since, but that cinnamon "treats diabetes" is certainly not proven. The practical benefit is simpler: flavor, less sugar in porridge and coffee, almost zero calories.

Coumarin: Doing the Math

The European Food Safety Authority (EFSA) set the tolerable daily intake of coumarin at 0.1 mg per kg of body weight: that is 6 mg a day for a person weighing 60 kg (as the Austrian agency AGES calculates) and about 7 mg for 70 kg. According to the UK Food Standards Agency, ground cinnamon was among the spices with the highest coumarin content: about 1,657 mg per kg, that is, roughly 1.7 mg per gram. This is an average across the samples surveyed; for a specific batch the figures may differ. Plugging in, four grams of such cinnamon is already about 6–7 mg.

What follows from this:

• A pinch in porridge or coffee is not a problem. The British survey showed that even "heavy consumers" of cinnamon usually have a coumarin intake below the tolerable level.
• If you put in a teaspoon or more every day, as a "sugar supplement", it's reasonable to choose Ceylon cinnamon.
• The French agency ANSES separately warns about coumarin overdose specifically from dietary supplements; children and people with liver problems should be more careful with them.

Seeds

Chia

It is mostly fiber, fats and ALA. It can help you get enough fiber and give satiety, but don't count on fat burning: in a 12-week randomized trial in overweight people (25 g of chia twice a day, 90 participants), no reduction in body weight or change in risk factors was found. A more recent review also sees no reliable effect on weight, although it mentions a small drop in blood pressure; the data are scarce.

Dry seeds shouldn't be eaten by the handful "dry": they swell a lot, and it's better to soak them in liquid. A reasonable serving is 15–30 g a day.

Flax

Here I'll correct the original version of this article: it can't be said that flax is "usually richer in fiber" than chia. On fiber, chia is not inferior. The real arguments for flax are different: price, ALA and lignans.

Ground flax is absorbed better than whole. In a trial in healthy adults (comparing flaxseed oil, ground and whole seed), ground seed and oil noticeably raised plasma ALA, while whole seed did not. A meta-analysis of controlled trials found a small reduction in blood pressure with flax, but critics note that it mixed whole and ground seed, so a strict conclusion is hard to draw. Ground flax oxidizes faster, so it's best stored briefly and cool.

A serving of about 10–20 g a day. Flax does not "balance hormones" or "cleanse the intestines"; it is an ordinary healthy part of the diet.

Sprouts and Microgreens

You need to distinguish sprouts (a seed germinated in a moist environment), microgreens (a young shoot grown in a substrate and cut later) and sprouted grain. Sprouting changes the composition slightly (some phytates and starch), but the advantage over ordinary whole grain is usually small. Microgreens are simply a fresh vegetable with a bright flavor, not a medicine.

The Real Risk of Raw Sprouts

The conditions for sprouting — warmth and moisture — are ideal for Salmonella, E. coli and other bacteria too, while the sprouts look perfectly normal. Sprouts are one of the few "healthy" categories where the risk has been demonstrated by individual outbreaks. Penn State University directly advises against giving raw sprouts to small children, older people and people with weakened immunity; pregnant women are usually advised the same. Cooking removes the problem.

Berries and Fruit Powders

Blueberries and Anthocyanins

Here there are decent data. A meta-analysis of 44 randomized trials and 15 cohort studies showed that purified anthocyanins slightly lowered LDL (about 5 mg/dL) and triglycerides; in cohorts, higher anthocyanin intake was linked to a lower risk of cardiovascular events. But: the effects are modest, many trials were short and small, much of the data is specifically on supplements, and cohorts say nothing about causation (people who eat berries often live healthier lives in other respects too). In other words, berries are good food, but "anti-cancer blueberry" remains an advertising image. And cheap frozen berries work no worse than fashionable ones.

Goji

They contain carotenoids and polyphenols; dried, they concentrate sugar. There is no convincing reason to consider goji noticeably healthier than blueberries, currants or cherries. A real practical caveat: several cases of raised INR (a measure of blood clotting) have been described in people who were taking warfarin and drinking goji tea or wine. These are isolated reports, not controlled trials, but people on warfarin should discuss goji with a doctor.

Acai

It has polyphenols, but usually it's a small serving of powder or a bowl to which banana, syrup, granola and nut butter are added. The benefit and calorie content of the dish are determined by its whole composition. I have no evidence of any special fat-burning or rejuvenating effect.

Berry Powders

They are convenient for storage and retain some of the compounds, but they don't replace a bowl of berries in volume, fiber and satiety.

Spirulina and Chlorella

Spirulina

Its protein content by weight is high (on the order of 60%), but a tablespoon (about 7 g) gives roughly 4 g of protein and about 20 kcal. It is a supplement, not a replacement for eggs, fish or legumes.

The main substantive point here is quality and safety. A study of commercial spirulina supplements (Turkey, 2026) showed a large spread in heavy metals between brands: overall the values met the standards, but one sample exceeded the acceptable risk index for all age groups except adults. Another possible problem is microcystins from stray cyanobacteria when cultivation is poor. A review by the US Pharmacopeia (USP) gave spirulina the safe class A, but that is not a guarantee of the quality of a particular jar. Harvard Medical School adds precautions: possible worsening of autoimmune diseases (theoretically), an effect on clotting, caution in phenylketonuria. Claims about "removing toxins" and "cleansing the blood" are not proven.

Chlorella

Protein, chlorophyll, a few minerals. The claim about removing heavy metals from the body rests on laboratory work and water-purification studies, not on good human trials. Some people feel nauseous, and cramps and diarrhea occur.

Matcha and Green Tea

Matcha is a powder of the whole tea leaf, so it has more caffeine and tea polyphenols than an ordinary infusion. It's a decent replacement for sugary drinks and a mild tonic drink. According to NCCIH, green tea as a beverage has no known safety problems for adults, while the effect on weight from catechins and caffeine is modest and varies from person to person; heart and cancer data are mixed. Serious caveats concern green tea extract capsules: cases of liver injury have been described, and drug interactions are possible (for example, with the statin atorvastatin and some other drugs). Tea, and especially concentrated matcha, can worsen sleep and cause anxiety; in large amounts, tea reduces absorption of non-heme iron.

Turmeric and Curcumin

Turmeric in dishes is a good spice. Curcumin in concentrated supplements is a different matter. According to NCCIH, meta-analyses show preliminary positive results for osteoarthritis pain, but higher-quality studies are needed, and for most other uses the evidence is insufficient. NCCIH also warns: a form of curcumin with increased bioavailability may harm the liver; such supplements often contain piperine from black pepper, and the composition of the products varies widely. Isolated cases of acute liver injury have been described. The spice in an ordinary serving is a different story, but "turmeric in capsules for everything" is not about nutrition.

Wheatgrass and "Greens" Powders

The blends often have an opaque composition: spirulina, chlorella, herbs, enzymes, probiotics, extracts; the dose of each is unknown and often small. A powder does not replace vegetables in volume, fiber, satiety and variety.

Brazil Nut

There really is selenium in it. The adult requirement according to NIH is 55 mcg a day. But the content in a single nut depends very strongly on the soil: different sources give a range from tens to hundreds of mcg per nut, and I could not confirm exact figures from ODS. The practical conclusion: one or two nuts are enough, while a handful every day can lead to excess (the generally accepted upper limit for adults is given as about 400 mcg a day). A rare example of a food where "more" really does mean "worse".

Maca

Maca is a root vegetable with carbohydrates and plant compounds. A 2010 systematic review found only four randomized trials on sexual function: in two there was an effect, in one there was none, and in one, in men with erectile dysfunction, there is one; the authors called the evidence limited. There are no reliable data on testosterone increases in the sources I found. Maca is not a "universal supplement".

Manuka Honey

This is a sweet product. The antibacterial properties of manuka honey may matter in specialized medical uses, for example in wound dressings, but in tea or porridge it doesn't become fundamentally healthier than ordinary honey.

Kale and Quinoa

Two "trendy" foods that were not in the original text but are worth mentioning.

Kale is simply cabbage, and a good one. For people with kidney stones it is often better than spinach, because it has noticeably fewer oxalates (different sources give different numbers, but the direction is the same). On the other hand, it is high in vitamin K: people taking warfarin don't need to avoid it, they need to eat it regularly, without sharp swings in amount.

Quinoa is a grain with a complete amino acid profile, but not a protein bomb: a cooked serving has on the order of 4.4 g of protein per 100 g and about 8 g per cup (data retold from the USDA via a secondary source). Saponins are bitter, so the grain is rinsed. Buckwheat and oatmeal are cheaper and usually no worse.

Fermented Foods

Among trendy topics this is almost the only one with an interesting randomized trial. In a Stanford study (36 healthy adults, 10 weeks), the group eating yogurt, kefir, kimchi, fermented vegetables and kombucha gained greater gut microbiota diversity and a decrease in several inflammatory proteins, while the high-fiber group did not show such an effect (possibly because of the duration). The sample is small, and markers were measured, not diseases. But kefir and sauerkraut cost pennies, and this is a good example: a "superfood" can be cheap and local.

Three Groups: What's Worth Your Money

Real Nutritional Value

Foods that provide a tangible amount of protein, fats, fiber, vitamins or minerals in an ordinary serving: legumes, oatmeal, buckwheat and whole grains, nuts and seeds, fish, eggs, fermented dairy and fermented vegetables, vegetables and berries. They can be checked against their composition.

A Small Real Benefit, Inflated by Advertising

Goji, acai, spirulina, chlorella, maca, moringa, wheatgrass, powders. There may be a benefit, but the servings are 3–10 g, and it is neither unique nor proportional to the price.

Almost Decorative Additions

A spoonful of powder in a smoothie, a few sprouts on top, 1–2 g of berry powder, a pinch of herbal blend. That's not necessarily a deception: flavor and color are also a value. But calling this a significant source of protein, iron or omega-3 is dishonest.

How to Check a Product

1. Look for a specific name: the Latin name of the plant, the species, the origin. "Herbal extract" is not a name.
2. Check the dosage: if a blend has ten ingredients and no gram amounts, there is nothing to evaluate.
3. Look at the form: whole, powder and extract are different things.
4. Look for independent laboratory testing: heavy metals, microbiology, algal toxins, pesticides, conformity with the declared composition.
5. Don't confuse organic with proven benefit: it is about the method of production, not about the effect and not about the absence of contaminants.

What It Makes Sense to Buy

Good value for benefit and price: ground flax, ordinary seeds and nuts, frozen berries, legumes, whole grains, fish, eggs and fermented dairy, fermented vegetables, greens and cabbage, ordinary green tea, turmeric as a spice. Most people regularly don't need expensive powders of acai, goji, wheatgrass, spirulina, chlorella, maca, or blends of dozens of "super-ingredients".

Bottom Line

Chia remains seeds, goji a dried fruit, acai a berry, matcha a concentrated tea, spirulina an optional protein supplement, and microgreens a young vegetable. That is no reason to despise them: many of them are tasty and healthy. It is a reason not to pay for a legend.

The most practical conclusion is boring: the foundation of the diet is vegetables, fruit, legumes, whole grains, eggs, fish, meat, dairy and fermented foods, nuts and seeds. Everything else is a seasoning for flavor, convenience or curiosity. Not a replacement for food and not a treatment.

Sources

• Superfoods or Superhype? — Harvard T.H. Chan School of Public Health
• What makes superfood so super — UC Davis
• Was the USDA right to drop its online ORAC database? — NutraIngredients
• Superfood claims to be banned — Fruitnet
• Cinnamon for diabetes mellitus — Cochrane review (PubMed)
• Beware of overconsumption of herbal supplements containing coumarin — ANSES
• Coumarin — AGES
• Survey on the consumption of cinnamon containing foods and drinks — UK Food Standards Agency
• Seeds, chia seeds, dried (mirror of USDA FDC data 170554)
• Chia seed does not promote weight loss or alter disease risk factors in overweight adults (PubMed)
• Bioavailability of ALA after three forms of flaxseed (AGRIS)
• Flaxseed consumption may reduce blood pressure: meta-analysis (PubMed)
• What you should know about sprouts — Penn State Extension
• Anthocyanins, anthocyanin-rich berries and cardiovascular risks: meta-analysis (PMC)
• Goji berry and warfarin case report — Toxicology Reports (DOAJ)
• Is Spirulina safe in terms of heavy metals? A public health risk assessment
• United States Pharmacopeia safety evaluation of spirulina (PubMed)
• Is spirulina good for you? — Harvard Health
• Turmeric — NCCIH
• Green tea — NCCIH
• Selenium — NIH Office of Dietary Supplements
• Maca for improving sexual function: a systematic review (PMC)
• High oxalate greens and kidney stones — NutritionFacts
• Warfarin and vitamin K — Alberta Health Services
• Quinoa, cooked (retelling of USDA data)
• Fermented-food diet increases microbiome diversity and lowers inflammation — Stanford Medicine