Did you know your thyroid hormones can affect your bone strength? We think of our bones as fixed, solid structures, but actually we move minerals in and out of them all of the time, and the number of cells we have in each bone can go up and down. As we get older, our bones can weaken, and one of the things that can influence bone strength is a thyroid hormone called calcitonin.
Calcitonin, thyroid and bones
Bone mineral density is affected by two different hormones; calcitonin and PTH. Calcitonin is released by the thyroid gland instructing calcium to enter your bones to increase bone tissue. Parathyroid hormone (PTH) does the opposite, instructing your bones to release calcium into your blood, thereby reducing bone tissue. PTH is released from your parathyroid glands which are tiny and nestled in your thyroid, which is level with your throat. You continually release both calcitonin and PTH, and the ratios of each will determine whether you are increasing or losing bone strength.
Whether your thyroid gland and parathyroid gland decide to add to or take from your bones’ mineral reserves is a complex decision The process takes into account the levels of calcium, magnesium, phosphorous, zinc and other bone minerals in your bloodstream that are needed elsewhere by your body. This includes an assessment of the pH of the cells all over your body. If any of them are at risk of becoming too acidic, calcium is released from your bones as calcium can very quickly keep them in range, as calcium is alkalising. The decision is also influenced by the levels of other hormones, such as oestrogen and testosterone.
So you need your thyroid gland to be in good working order to make enough calcitonin to keep your bones strong. Even just mildly low thyroid levels, which is called subclinical hypothyroidism, are associated with low bone density and a higher risk of fracture.
Food for calcitonin
Calcitonin is released when you have high levels of both calcium and amino acids in your bloodstream. Calcitonin is also made from amino acids, which you can get by having adequate proteins in your diet. If you eat dairy, that’s a fairly well-known source of all the amino acids plus calcium. If you eat little or no animal products, then you can actually get the same nutrients from eating a variety of nuts, seeds and pulses (beans, peas and lentils).
Plant-based foods for thyroid and bones
Almonds, brazil nuts and sesame seeds are particularly high in calcium while providing some of the amino acids you need. Adding different kind of beans will give you the other amino acids you require, plus they are also a great source of calcium. Tofu and other soya products will give you all the amino acids you need in your diet plus plenty of calcium.
So whatever your diet, you should be able to get everything you need to make and trigger the release of calcitonin, the thyroid hormone that keeps your bones strong.
Mun, H.C., Leach, K.M. and Conigrave, A.D., 2019. L-amino acids promote calcitonin release via a calcium-sensing receptor: Gq/11-mediated pathway in human C-cells. Endocrinology, 160(7), pp.1590-1599.
Williams, G.R. and Bassett, J.D., 2018. Thyroid diseases and bone health. Journal of endocrinological investigation, 41(1), pp.99-109.