Q: While this style of eating and living makes sense to me, I am still left with the question of how to meet the Recommended Daily Allowance (RDA) for calcium. From all I’ve read on the subject, it’s not possible to reach the RDA with vegetable sources (unless you include fortified soy or rice milk). Since dairy isn’t part of your scheme, how does a person meet the RDA? Or do you disagree with the RDA?
- Indeed, we relieve the RDA is higher than what you would need in a Palaeolithic type diet, because:
- The absorption rate from brassica vegetables (e.g. Kale) is slightly higher than from milk (see attached paper) and as so (and also because they have numerous health benefits), we advise the daily intake of these foods.
- A diet with lots of vegetables and fruit is net base yielding and in contrast a diet high in grains, cheese and salt and low in fruits and vegetables (which is a characteristic of the American way of eating) is net acid yielding and this increases calcium excretion.
- The Paleo Diet is a High protein diet and this increases intestinal calcium absorption1, 2 and has an anabolic effect on bone3, particularly in the context of a net base yielding diet3.
- By avoiding grains, you decrease anti-nutrient intake, such as phytates, which decrease magnesium4, calcium5 and zinc5 absorption.
- The Paleo Diet is a Low Glycemic Load diet and as so, it does not promote Hyperinsulinemia as a high grain diet. It has been known since the year I was born (1975) that high blood insulin levels cause urinary calcium loss6.
- Milk has a high Insulinotropic effect, and as so it may lead to an increase in urinary calcium excretion, for the reason outlined in point 5.