THE familiar phrase “you are what you eat” is only really partly true. A more accurate version would be “you are what you absorb”. We can eat all the healthy foods in the world, but if we are unable to absorb and use their nutrients properly, we’re at a bit of a loss.

Nutrient absorption can be affected by stress, digestive problems, medications, and naturally occurring plant compounds like phytates and tannins.

The heartburn and indigestion medications Omeprazole, Nexium, and Lansoprazole are used by millions of people every day. They work by blocking stomach acid production and they do help to ease heartburn. But as a side effect they impair absorption of protein, iron, vitamin B12 and zinc. Many older people who use PPIs are already at risk of B12 deficiency and it’s important to have B12 levels checked regularly.

Stress and digestive problems can affect levels of stomach acid production and the balance of beneficial bacteria in our guts. Healthy digestion is crucial for nutrient absorption, so do take time to relax at mealtimes, chew food thoroughly, and regularly include probiotic foods such as sauerkraut, kefir, natural yoghurt and kimchee to support your gut bacteria.

Plants naturally contain their own self-defence mechanisms in the form of tannins and phytates. These compounds protect the plant from pests, moulds, and diseases, but can interfere with how well we absorb nutrients.

For most people, their main source of tannins is tea. And a lot of people are strongly attached to their cuppa! Tannins can interfere with your uptake of iron, calcium, zinc, and magnesium – important minerals for energy, bone health, mental wellbeing and more. Rather than stopping tea altogether (though in some cases that is helpful) just make sure there is a gap of at least an hour after meals before enjoying a brew. A good alternative to regular tea is Rooibos or Redbush tea which is naturally low in tannins.

Phytates are widely found in grains, nuts, seeds, and beans. Soaking these foods helps to breakdown the phytates and aid nutrient absorption, as does sprouting and fermenting. Nuts and seeds can be dried again after soaking you don’t have to eat them wet, while grains and beans can be soaked before cooking.

Sally Duffin is a registered nutritionist (MBANT). Find her online at or join the Facebook group ‘Nutrition in York’