MEPX
Chapter 8 of 10All chapters
  1. 1What food is made of
  2. 2Energy balance
  3. 3What is broadly agreed
  4. 4Why the science is hard
  5. 5Common myths
  6. 6Reading labels
  7. 7Diets
  8. 8Supplements
  9. 9Water, salt and alcohol
  10. 10Practical and honest

Chapter 8 of 10

Supplements

A large industry, narrow evidence.

When they help

Diagnosed deficiencies, vitamin D where sunlight is limited, folate in pregnancy, B12 on a vegan diet, and iron where a clinician has identified need.

  • Multivitamins show little benefit in well-fed populations.
  • Fat-soluble vitamins can accumulate to harmful levels.

Regulation

Supplements are regulated far more loosely than medicines in most countries. Contents can differ from the label, and interactions with prescribed drugs are real.