WHAT TO REMEMBER :
- Calcium is the most famous element in the world of nutrition, it is associated with good bone health.
- In recent years, there has been a debate on the need for calcium intakes and their possible decline.
- It now seems certain that our intakes through food are sufficient, and that supplementation is not necessary or even harmful !
If there is ONE chemical element you have heard about, it is Calcium. And this regardless of your age, your level of interest in nutrition, your origin and your place of residence. You MUST ingest enough calcium every day of your life, whether you are small ("no more Swiss if you want to grow up") or large ("you know at my age, I have to strengthen my bones. But in recent years, a different discourse seems to be emerging: not only do calcium tablets break teeth, but they would cause much more damage inside, without bringing anything to your bones... So we would have been lied to?? To see more clearly, a return to the fundamentals is needed.
Calcium - the basics
If we have often heard about calcium, it is because it is indeed essential to the functioning of the human body, not just your bonesof which it is one of the essential elements. Calcium is essential for teeth, blood coagulation, muscle contraction, oocyte activation, but also nerve transmission, and at the elementary level it is part of the alkaline earth, just below magnesium in the periodic table of elements. And this proximity is not insignificant, calcium being a close cousin of magnesium (a little larger and softer than magnesium), they still look a little similar and are therefore often found in the same places in the human body. And those who have been following us for a while know that: 60% of the Magnesium present in our body is found in the bones, with calcium: CQFD (computer graphics).
How much calcium should I take each day ?
Since calcium is so important, and so much studied, then you also think that we must surely know EXACTLY how much we need to take it every day. Well... not really. In France, the ANSES lowered its recommendations in 2016, from more than one gram to 860 mg in young adults and 750 mg in confirmed adults. The US also has relatively high NRVs: 1g/day for adults, and 1.2g/day for women over 50 years of age (the same values as in France a few years ago). Women in menopause are entitled to preferential treatment because the hormonal changes associated with this period of life cause a deceleration of their bone production. The WHO (World Health Organization), on the other hand, speaks of an optimal intake of 520mg/day, and has done so for years and on a constant basis (3).
Nice difference, and especially interesting change on the part of the ANSES, since at the same time, the new PNNS (National Nutrition and Health Plan) has updated the scientific recommendations on food, (you know, the famous "5 fruits and vegetables per day", "less meat", "less sugar"...). And dairy products, whose role has always been presented to us as calcium intake, have simply...disappeared. To make matters worse, more and more doctors are challenging the role of osteoporosis in recurrent fractures in the elderly and the very role of calcium in bone strength (4,5,6).If it was usual to see your loved ones over 50 crunch to death from the famous calcium tablets to take care of their bones, (you will have understood that we have a tooth against these tablets) things seem to be changing. It is indeed increasingly clear that it is the co-factors, in this case vitamins K and especially vitamin D, that must be taken into account. These allow the body to fix the available calcium on the bones (8,9).
A Calcium / Magnesium link
But that's not all: too much calcium can also have significant negative effectsand which are beginning to be listed in the literature. The one that comes up most often is increased cardiovascular risk (via calcification of the arteries), nervousnessand more than kidney stones, of course, (10),(11),(12).
Besides, do you remember the famous cousin relationship between calcium and magnesium? Well, you should know that the calcium/magnesium ratio is nowadays one of the most relevant indicators. The latter is supposed to be optimal at 2:1 in humans (2 calcium for 1 magnesium). However, the average ratio of our contributions today is closer to 10:1 (!!!), that is, that of... cow's milk, necessarily (13) !
And this imbalance may partly explain the magnesium deficiency in most of us because the Calcium (Ca2+) and magnesium (Mg2+) ions use the same channel (DMT1) to enter the cells. And if we clog the canal with Calcium, well magnesium and especially iron, can devote themselves to their favorite activity: drop us and leave before we can assimilate them (14).
Be careful, we are talking about effects related to calcium intake in nutraceuticals, not to calcium intake through food. Don't throw away that good reblochon that's just starting to smell right.
Calcium supplementation : the team's opinion
No, you probably don't need to take extra calcium, you certainly take enough from your diet.
- And yes, supplementation may cause more harm than good, so no calcium-containing nutraceuticals in our country (#LeMulti).
- For strong bones :
- Make sure you have enough co-factors, Vitamins D3 and K, because they will help your calcium make the bones.
- Take magnesium ! It works in tandem with Vitamin D to strengthen your bones and helps to rebalance the Ca/Mg ratio.
- Avoid foods that are too acidic. It has not been detailed here, but calcium could contribute to the acid-base balance, and it is siphoned from the bones if necessary to regulate acidity (there is currently a debate in the scientific community on this point, the most daring can throw themselves into the battle (15)).
- And above all: BOU-GEZ. The main motor for bone renewal is physical activity (16).
1. Piste et al., Calcium and its role in the human body, International Journal of Research in Pharmaceutical and Biomedical Sicences, 4 (2), 2013, 659-668
2. https://www.anses.fr/fr/content/le-calcium
3. “Vitamin and mineral requirements in human nutrition, World Health Organisation, Second Edition 2004”
4. https://www.health.harvard.edu/staying-healthy/calcium-supplements-for-bone-health-do-you-really-need-them
5. Kukuljan et al., Independent and combined effects of calcium-vitamin D3 and exercise on bone structure and strength in older men: an 18-month factorial design randomized controlled trial, Journal of Clinical and Endocrinal Society, 96 (4), 2011, 955-63
6. Jarjou et al., Calcium intake of rural Gambian infants: a quantitative study of the relative contributions of breast milk and complementary foods at 3 and 12 months of age, European Journal of Clinical Nutrition, 66 (6), 2012, 673-677
7. Guide et documents officiels PNNS4 : https://www.mangerbouger.fr/PNNS/Guides-et-documents
8. Bikle, Vitamin D and Bone, Current Osteoporosis Report, 10 (2), 2012, 151-159.
9. Weber, Vitamin K and Bone Health, Nutrition, 17 (10), 2001, 880-887
10. Reid et al., Calcium and Cardiovadcular Diesease, Endocrinology and Metabolism, 32 (3), 2017, 339-349
11. Anderson et al., Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10‐Year Follow‐up of the Multi‐Ethnic Study of Atherosclerosis (MESA), Journal of the American Heart Association, 11;5 (10), 2016
12. Li et al., The good, the bad, and the ugly of calcium supplementation: a review of calcium intake on human health, Clinical Interventions in Aging, 13, 2018, 2443-2452
13. Oh., Magnesium in Milk, International Dairy Journal, 71, 2017, 89-97
14. Lonnerdal, Calcium and Iron Absorption – Mechanisms and public health relevance, International Journal for Vitamin and Nutrition Research, 80 (4-5), 2010, 293-299
15. Frassetto et al., Acid Balance, Dietary Acid Load and Bone effect – A controversial Subject, Nutrients, 10 (4), 2018, 517-525
16. Carter, Physical Activity and Bone Health, Missouri Medicine, 111 (1), 2014, 59-64
