The best supplement is on your plate: what food can cover

The short answer

The healthiest way to take your vitamins and minerals is to eat them. That is not just our view: UK and EU law (in England, the Food Supplements Regulations 2003, based on Directive 2002/46/EC) require every food supplement to state on the label that it should not be used as a substitute for a varied diet. The NHS says most people do not need vitamin supplements, and Germany’s BfR considers them generally unnecessary for healthy people who eat a varied, balanced diet. There are clear exceptions, which we cover below, but the starting point is your plate.

Why food comes first

• One plate covers several nutrients at once. A serving of Spanish spinach with chickpeas gives about 170 mg of magnesium and 7.4 mg of iron: close to half the NRV of both.
• It is hard to overdo it with ordinary food. Upper limits for magnesium (250 mg a day for EFSA, 400 mg for the NHS) apply to supplements, not to the magnesium naturally in food.
• No small print. With a supplement you have to check the form, the dose and the limit. With a bowl of lentils, you don’t.

What food can cover, nutrient by nutrient

Behind the table

Magnesium, zinc and vitamin C. These are the easy ones. Half a raw red pepper gives 96 mg of vitamin C, and a 30 g handful of pumpkin seeds about 165–178 mg of magnesium, depending on whether they are roasted. The NHS puts adult magnesium needs at 300 mg a day for men and 270 mg for women; EFSA’s figures are a little higher (350 and 300 mg). The details are in magnesium-rich foods and vitamin C and zinc in winter foods.

Iron. Pulses, meat and shellfish contain plenty, but the body absorbs only part of it: 14–18% from mixed diets and 5–12% from vegetarian diets, according to the NIH. Vitamin C in the same meal helps; we show how in iron-rich foods. If you feel tired, read iron supplements and tiredness before buying anything.

Vitamin D. In the NIH’s words, “few foods naturally contain vitamin D”. Our calculations show that even oily fish three times a week plus an egg a day covers at most about half of what EFSA considers adequate (15 µg), or three quarters of the UK’s 10 µg. The rest comes from sunlight, which in the UK is too weak from about October to March. That is why the NHS advises everyone to consider a 10 µg supplement in autumn and winter. We work it out in vitamin D foods; the winter gap is covered in vitamin D in winter.

Vitamin B12. If you eat meat, fish, eggs or dairy, food is usually enough. On a vegan diet it is not: the NHS notes that vegans may not get enough, and the Vegan Society and the German Nutrition Society recommend fortified foods or a supplement. More in who needs a B12 supplement.

Folic acid. The NHS recommends 400 micrograms of folic acid a day while you are trying to get pregnant, ideally from three months before, and for the first 12 weeks of pregnancy. Here food does not replace the supplement.

Omega-3. The NHS advises at least 2 portions of fish a week, 1 of them oily; EFSA considers 250 mg of EPA and DHA a day adequate, and fatty fish is the main source. If you eat no fish, algae oil is the alternative: see omega-3 fish oil vs algae oil.

Creatine. According to researcher Richard Kreider (Texas A&M), a pound (450 g) of red meat or fish provides about 1 g of creatine, and the body makes about 1 g a day. Reaching the 3 g a day in the authorised claim from food alone would take well over 1 kg of meat or fish a day. More in our creatine guide.

When a supplement does make sense

• It is autumn or winter in the UK: the NHS advises everyone to consider 10 µg of vitamin D a day.
• A blood test shows a deficiency of iron, vitamin D or B12. Your GP will set the dose and duration.
• You are vegan: B12 is not optional.
• You are trying for a baby or are in the first 12 weeks of pregnancy: folic acid.
• You get very little sun: food is unlikely to cover vitamin D.
• You have a child aged 6 months to 5 years: the NHS advises daily vitamins A, C and D (free through Healthy Start if you qualify).
• Your GP advises it because of an illness, a medication or a specific situation.

Outside those cases, check your plate before you buy a jar.

How to read our food tables

Each guide in this series gives:

• Figures per real serving, not per 100 g: a handful of seeds, a plate of pulses, a tin of sardines.
• The % NRV, the reference value UK and EU labels use.
• The legal threshold (UK and EU). A food may be advertised as a “source of” a nutrient if it provides at least 15% of the NRV per 100 g, and as “high” in it from 30%.
• Ranges when official databases disagree, instead of a falsely precise number.
• Calculated recipes using the same data.

Values come from official food composition databases (USDA, Spain’s BEDCA and France’s CIQUAL), and NutriMetrics does the calculations. UK daily needs come from the NHS.

The series

1. Magnesium-rich foods: how much each serving gives you
2. Iron-rich foods: how much per serving and how to absorb it
3. Vitamin C and zinc: the winter foods that give you the most
4. Vitamin D foods: how much you can cover by eating