This is one of the biggest areas of concern when people (especially women, who are at greater risk for developing osteoporosis) switch to a paleo diet. If we aren’t eating any dairy products, how do we make sure we get enough calcium??? It is one of the many pervasive bits of misinformation that we battle against (akin to saturated fat causing heart disease): that we need to consume dairy products to protect our bones. This simply isn’t true. And it isn’t true for three reasons. First, dairy is hardly the only source of dietary calcium out there. Second, the calcium from other food sources is actually more absorbable than the calcium in dairy. Third, bone health is determined by a whole lot more than just calcium.
Most importantly, dairy products are not the only good source of calcium out there. In fact, fruits, vegetables, nuts, seeds, meat, and seafood all contain calcium. Let’s compare some paleo foods against a glass of milk:
|Food||Calcium / Serving|
300 mg per 1 cup
|Collard greens||210 mg per ½ cup|
|Kale||205 mg per ½ cup|
|Bok Choy||190 mg per ½ cup|
|Figs||135mg per 5 figs|
|Turnip Greens||104 mg per ½ cup|
|Spinach||99 mg per ½ cup|
|Almonds||93 mg per ¼ cup|
|Sesame Seeds||51 mg per 1 Tbsp|
|Sardines (with bones)||213mg per 2oz|
|Salmon (with bones)||241 mg per 4oz|
|Orange||52mg per medium orange|
|Mushrooms||18 mg per 2oz|
Not only do fruits, vegetables, nuts, seeds and seafood contain substantial amounts of calcium, there is scientific evidence that you actually absorb more calcium from cruciferous vegetables (like kale) than you do from dairy! Cruciferous vegetables (like kale, cabbage, broccoli, collard greens, turnip greens, etc.) may actually be your best source of dietary calcium. And in fact, several studies show that fruit and vegetable intake correlates much more strongly than dairy intake with bone health–yes, to prevent osteoporosis and look after your bones, eat your veggies!
Other great sources of dietary calcium include: green leafy vegetables, nuts (almonds especially), seeds (especially sesame seeds), figs, oranges, dried apricots, okra, bok choy, seafood (especially when you eat the bones like canned salmon or sardines), and to a lesser extent, all fruits and vegetables. Organ meat and bone broth are also excellent sources of not only calcium, but magnesium and phosphorous, which are also critical for bone health. Yes, you need other minerals to make bones too! This might be one of the reasons why higher vegetable intake correlates with better bone health–vegetables also provide these other essential minerals.
Bone health is about much more than calcium and the other minerals used to physically make up bone. Not only do you need minerals as raw materials, but fat soluble vitamins (A, D and K2 in particular) are essential regulators bone mineralization. Where do you get these essential fat-soluble vitamins? Seafood, dairy fat from grass-fed cows (meaning grass-fed ghee, butter, or heavy cream), and the fat from grass-fed and pasture-raised meat. Because the majority of people still don’t source meat and dairy from pasture-raised sources, for most people the dominant dietary source of these vitamins comes from seafood. No wonder high seafood intake also correlates with bone health!
You know what else is critical for bone health? Weight bearing exercise–meaning exercise where you move your own body weight around, like walking!
Basically, if you are eating plenty of fruits and vegetables (especially cruciferous vegetables) and seafood, sourcing the best quality meat you can, maybe incorporating some bone broth into your diet, and getting some exercise (even if it’s just walking), you are doing a great job of looking after your bones.
Also see my post about The Great Dairy Debate.
Heaney RP and Weaver CM. Calcium absorption from kale. Am J Clin Nutr April 1990 vol. 51 no. 4 656-657
Charoenkiatkul S, et al. Calcium absorption from commonly consumed vegetables in healthy Thai women. J Food Sci. 2008 Nov;73(9):H218-21.
New SA et al. Dietary influences on bone mass and bone metabolism: further evidence of a positive link between fruit and vegetable consumption and bone health? Am J Clin Nutr. 2000 Jan;71(1):142-51.
Chen YM et al. Greater fruit and vegetable intake is associated with increased bone mass among postmenopausal Chinese women. Br J Nutr. 2006 Oct;96(4):745-51.
New SA. Intake of fruit and vegetables: implications for bone health. Proc Nutr Soc. 2003 Nov;62(4):889-99.
Zalloua PA et al. Impact of seafood and fruit consumption on bone mineral density. Maturitas. 2007 Jan 20;56(1):1-11. Epub 2006 Jun 27.