Animal protein and bone loss: what's eating you?
There are copious scientific studies showing that people eating a diet high in dairy products have high bone loss. There are incontrovertible links between animal protein and bone loss. And conversely, that fresh fruit and vegetables protect and strengthen our bones. A huge analysis of 34 surveys from 16 countries found that 70 per cent of all fractures resulted from eating animal protein (Abelow et al, 1992). Not satisfied with that, another scientific team tested the same theory in a seven-year study of 1,035 women. They found that those with diets high in animal protein had almost four times more bone loss – and a 3.7 times higher risk of hip fracture – than women who ate the least amount of animal protein (Sellmeyer et al, 2001). A highly-regarded study of more than 120,000 women lasting 12 years showed that eating more than 95g of protein a day significantly increased the risk of forearm fracture (Feskanich et al, 1996).
And there’s more! A gargantuan study of almost 80,000 women in the USA led by scientists at the Department of Nutrition, Harvard School of Public Health, examined whether by increasing your milk intake you can reduce the risk of fractures. It found that not only does milk not protect bones from fractures but that women drinking two or more glasses of milk a day increased their risk of hip fracture (Feskanich et al, 1997). A recent study looked at children and the growth of their bones and it concluded that animal foods, particularly meat, had a significant negative effect on bone mass increase (Zhang et al, 2010). And an important review of 58 different scientific papers examining whether high calcium or high dairy intake improves bone health in children was published in the highly esteemed Pediatrics journal. It concluded neither option gives even a modest benefit (Lanou et al, 2005). One of the authors of this review, Professor Amy Lanou, PhD, holds a doctorate in human nutrition from Cornell University and her book, Building Bone Vitality, makes clear that for healthy bones we must:
- Increase fruit and vegetable servings to six to 10 per day
- Avoid or limit protein from animal sources (no meat, dairy and so on)
- Exercise regularly (at least 30 minutes every day)
- Get adequate vitamin D through sunshine or a supplement
- Obtain calcium and other bone – healthy nutrients from plant sources
When we consume dairy, calcium floods our body and much of it is quickly lost in our urine because so much of it can’t be immediately used or stored. Animal protein and bone loss go hand in hand. Even though (animal) protein increases our absorption of calcium, this is not necessarily a good thing. The ongoing European Prospective Investigation into Cancer and Nutrition (EPIC) studied almost 9,000, 35 to 67 yearold women. It was carried out by the Department of Epidemiology at the German Institute of Human Nutrition and it showed that as animal protein intake increases, bone health deteriorates. Conversely, as vegetable protein increases, bones are found increasingly to be protected. This study accounted for age, weight, hormone replacement therapy, smoking, exercise, alcohol intake, menopausal status, education and occupation… in other words the scientists narrowed down the impact to the effects of protein alone (Weikert et al, 2005). When we eat healthy plant foods, we are not overwhelmed with excessive calcium but instead we get a steady supply throughout the day. Our body then uses what it needs without depositing excess calcium in the wrong places, risking kidney stones and hardening of tissues – including blood vessels which can increase the risk of heart attack. Also, when small amounts of calcium are absorbed into our blood, hormone regulation is more precise so that bone breakdown and build up is not overstimulated. It is vital that we eat enough calcium, as well as a host of other nutrients, for bone health, see page 42 for recommended amounts. However, osteoporosis is generally not a disease of low calcium. It is caused by many factors including bad diet (often with excess calcium and animal protein and low fruit and veg), smoking, alcohol consumption, low oestrogen or testosterone, lack of exercise and being underweight. Despite relentless claims by the dairy industry, milk is neither the only nor the best source of calcium. It takes strength to stand up against a lifetime of propaganda – but that is what we have to do in order to sweep aside the myth that dairy is the holy grail for strong bones and teeth. In fact, the opposite is true. In terms of diet, the biggest favour you can do for ‘dem bones is avoid dairy and all animal products and enjoy a wholefood vegan diet packed with fruit and vegetables, mushrooms, pulses, nuts and seeds and small amounts of vegetable oils.