Dairy Free Diets - Bone Health Risk?
A BBC headline last week suggested dairy free diets are a risk to bone health (due to low calcium intake). Should we be worried? Well... yes and no. Firstly the no. We have got along fine throughout most of human history without dairy - our bodies are designed to work optimally without it. Societies all over the world have much less dairy than we have in the UK and the US and many of them don't have an increased risk of conditions such as osteoporosis.
However (this is the yes bit!) we do need calcium in our diet, and if people cutting out dairy don't have a very varied diet they may be low in calcium. We need it for our bones but also for our muscles to work effectively. The UK government tells us we need around 700 mg of calcium a day. Some governments say much more - some less. But their figures are based on the assumption that not all of that calcium is going to be absorbed. Our actual biological need is between 300-500 mg. We get some in our water (very varied levels) but where else can we get it?
Good non-dairy sources include: Collard Greens/Kale (268 mg per cup); Almond Milk (381 mg per cup); Lentils (419 mg per cup); Sesame seeds (1404 mg per cup); Canned fish - especially if you eat the bones (sardines 569 mg per cup).
Interestingly not all dark leafy greens are created equal in terms of calcium. The calcium in spinach is less bio-available (ie it is not well absorbed) due to its oxalate content, which binds to calcium. Cooking leafy greens decreases oxalate content.
Similarly not all seeds are created equal. Pumpkin seeds have 61.4 mg vs sesame's 140.4 mg.
And finally the fibre and phytic acid content of pulses can reduce the bio-availability of calcium.
So that doesn't mean there is no point eating lentils, pumpkin seeds and spinach. They are home to lots of other great nutrients and soaking pulses and seeds reduces their phytic acid content and increases their availability to the human body. It does mean you need to eat lots of different things, both cooked and raw in order to get all the nutrients you need.
Other ways to improve bone health: Sodium uses up calcium so should not be consumed in excess; Vit K and D are also important for bone health; Probiotics help with general absorption - particularly phytic acid; weight bearing exercise is great for mineralising bones.
So is there any truth in the headline? Well - 50% of the calcium in cabbage, broccoli and kale is bio available when cooked, whereas approximately 30% of the calcium in milk is bio available. You do the maths..... However - you do actually have to eat your greens rather than just talk about it!
Top tip - put blanched and then frozen kale in your smoothie, add in a dessert spoon of sesame seeds, top it up with a cup of almond milk and then what ever else tickles your fancy (banana, sweet potatoes, coconut milk, cinnamon etc) ...job done.