Nutrition


You would be forgiven for thinking that food, once committed to your stomach, trundles along to carry out its job. However, your body doesn't have it that easy.

Even if your dinner successfully navigates the intricate processes required to digest and absorb nutrients into the bloodstream, the food itself might not have high bioavailability - the extent to which nutrients can be used by the body.

But one way to support nutrient absorption and get more from what you eat is to focus on positive pairings. Here are our top five.

1. Vitamin C and non-haem iron

Haem iron (found in red meat, shellfish, poultry and fish) is usually absorbed well and little affected by other foods eaten in the same meal.

On the other hand, the absorption of non-haem iron (found in non-animal sources), is greatly influenced by meal composition. Vitamin C, however, captures non-haem iron and stores it in a form that’s more bioavailable.

One study found that taking 100mg of vitamin C with a meal increased iron absorption by 67%.

Try: Red pepper dipped in hummus; a squeeze of lemon over lentil daal; tofu stir fry.

2. Curcumin and piperine 

The active ingredient in turmeric, curcumin is widely known for its antioxidant and anti-inflammatory properties. Yet it can be difficult to ingest enough of it to reap any of the supposed health benefits.

Adding a dash of black pepper, however, could help. One study found that pairing 20mg of piperine with 2g of curcumin increased the bioavailability of curcumin by 2000%.

Try: A dash of black pepper on your turmeric latte or over a curry.


One study found that taking 100mg of vitamin C with a meal increased iron absorption by 67%


3. Vitamin D and calcium

Calcium and vitamin D work together to protect bone health; calcium helps to build and maintain bones, whilst vitamin D helps your body to effectively absorb calcium. Therefore, even if you are getting lots of calcium, it may be going to waste if you are deficient in vitamin D.

Try: Leafy greens served with oily fish such as salmon or mackerel.

4. Fat-soluble vitamins (A, D, E and K) and fat

Vitamins are grouped into those that are water-soluble and those that are fat-soluble. Vitamins A, D, E and K, therefore, have greater bioavailability when consumed with dietary sources of fat.

Try: Carrots dipped in hummus; kale and avocado salad; full fat Greek yoghurt topped with a handful of nuts and seeds.

5. Vitamin D and magnesium

A randomised trial involving 250 people has also found that magnesium appears to optimise and regulate vitamin D levels. Researchers were interested in the role of magnesium after it was observed that people synthesise vitamin D differently, with levels not rising in some people even after being given a high dose. Lead author Qi Dai, MD, PhD, said that magnesium deficiency “shuts down” the pathway for vitamin D to be synthesised and metabolised.

Try: Salmon and spinach salad, with a sprinkling of pumpkin or chia seeds. Chicken and brown rice served with leafy greens.


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