Four elements - calcium, phosphorus, magnesium, and sulphur - plus sodium and potassium which control both the water balance and electrical signalling in the body - are called macro-minerals because we need relatively large amounts each day (300–3,000mg). Sulphur is largely ignored because it’s a component of many proteins so, if you’re not lacking protein you’re unlikely to be lacking sulphur.
The remaining elements are called trace minerals because we need only traces each day (30mg–30mcg). But all these minerals are required in tiny amounts compared to carbon, hydrogen and oxygen.
In the body, minerals are mainly used to regulate and balance our body chemistry; the exceptions are calcium, phosphorus and magnesium which are the major constituents of bone.
For example, a 63.5kg (10 stone) man needs 400g of carbohydrate a day but only 40mcg of chromium, which is less than a millionth of the amount. Yet chromium is no less important.
The main minerals to be mindful of
Although we need all the minerals mentioned above in order to be healthy, there are some that vegans need to be particularly aware of, not because you cannot get them from a plant-based diet, as is the case with vitamin B12, but because you need to be mindful about what you eat in order to achieve enough. The most important in this respect are iron, iodine, selenium, calcium, magnesium and zinc. The last two are not more deficient in a vegan diet than in an omnivorous one; they are just the most commonly deficient in everyone’s diet, and the most important for health.
Selenium and iodine are found in the richest quantities in seafood hence seaweed is an excellent source of both these minerals. Iron, like zinc, is abundant in ‘seed’ foods, including beans, lentils, nuts and seeds, so it can be well supplied in a healthy vegan diet. The iron found in plant-based foods is not as bioavailable as that found in meat, called haem iron, but it can be made more bioavailable (how to do this is explained on page 00). Calcium, although found richly in dairy products, is also in plentiful supply in seed foods, such as almonds, and many nut milks. Calcium is no more bioavailable from dairy milk than plants, as long as you have sufficient vitamin D. Magnesium is abundant in a healthy vegan diet and of great importance to health.
I explain this in great detail in my book Optimum Nutrition for Vegans.
OPTIMUM NUTRITION FOR VEGANS
If you are finding it challenging being a healthy vegan or are considering becoming vegan/more plant based but lack the confidence to take the leap, then try my new book Optimum Nutrition for Vegans published in December 2020 (Piatkus).
I explain how to get enough protein and brain fats, control your sugar and energy, ensure you maintain sufficient vitamin and mineral levels and other small steps that maintain a good overall health.
I also cover what to eat, and in what combination, to achieve the best of health with clear principles for how to get enough good quality protein by combining foods, slow release carbs and essential fats. Plus 100 delicious easy vegan recipes that will nourish your body and your brain.