Do we need to be drinking cows milk to strengthen our bones?
One of the biggest nutrition myths is the belief that we have to have milk for strong bones. Calcium is indeed important for bone health, but this was actually a government backed marketing campaign to unload surplus milk supplies as a result of over subsidisation and has somehow stuck.
Since it’s hard to milk a wild animal, dairy consumption as a dietary staple is actually a new thing for humans - before agriculture and the domestication of livestock 10,000 yrs ago, the only milk we would have consumed would be breastmilk as an infant. Human bone health actually started to decline after we started to consume cows milk this much….actually, countries which have the highest animal milk intake have the highest levels of osteoporosis (which is loss of bone density).
This might be because countries that drink a lot of cows milk also eat a lot of other animal protein. Another view is that the high protein content (3x) in cows milk compared to human milk - which is great if you are a baby cow, isn’t great for us, the high sulphur amino acid content of cows milk can increase sulphuric acid formation which in turn actually leaches calcium from the bones.
So where should we get our Calcium from?
We should prioritise plant based food sources, and make sure we optimise our vitamin D and K levels (the vitamin D spray I recommended is with vitamin K).
Just another reason to eat dark leafy green and brassica/cruciferous veggies - they are super high in Calcium (and actually absorption of calcium is 2 x higher from cruciferous veggies compared to from dairy/milk).
Other good sources of calcium are nuts and seeds (sesame, almonds), beans (soy/edamame, haricot), herbs and spices (sage, coriander) & sardines (including the tiny bones)
Calcium absorption is controlled by vitamin D, so with low vitaminD levels you can have low Calcium levels in the blood. To compensate for this, Calcium is taken out of your bones and put into the blood stream. This causes loss of bone mineral density - osteoporosis/osetomalacia.
Calcium is good for a lot more than just bone health. Its important for muscle contraction, blood clotting AND is a required co-factor for the conversion of tryptophan to serotonin - i.e. it helps make us feel happy and is especially important for mood related PMS symptoms and the bloating + water retention that comes with PMT
Calcium absorption is also blocked by phytates (a molecule found in lentils) and oxalates (spinach, swiss chard, beetroot, rhubarb). Eating too fast/not chewing enough or medications like omeprazol (proton pump inhibitors for acid reflux) cause low stomach acid which also inhibits absorption (as the hydrochloric acid in the stomach dissolves calcium salts).
Supplements of Calcium are shown to be Ineffective at preserving bone mineral density and come with side effects (kidney stones, soft tissue calcification), better off getting good amounts of sunlight and plant based calcium sources.