Non-dairy sources of Calcium for Women with Osteoporosis and Osteopenia
If you have been diagnosed with osteoporosis or osteopenia, you probably want to maximize your diet to increase your chances of building bone. Calcium is one essential component of strong bone.
But what if dairy isn’t for you?
What are good sources of non-dairy calcium?
Is spinach a good source? Should it be cooked?
These are a few of the questions that came up in my free Facebook group, Osteoporosis, and Osteopenia Exercise Support. It started when I asked everyone what their favorite non-dairy calcium-rich food was.
The general guideline for women over 50 is to consume 1200 mg of calcium/per day.
There were a lot of great responses and good ideas.
Here are a few of them (in no particular order):
Broccoli
Almonds
Arugula
Collard greens and Kale
Chia seeds
Soy milk
Bok Choy
Flax seed
Almond milk
Figs
Seeds, like sunflower or sesame seeds
Orange juice - fortified
The one that caused a bit of confusion was spinach.
I listed it as a good source but was quickly questioned about whether it was better in a cooked state, or if it was a good source at all.
Here's what I found out (remember, I am not a registered dietician).
Spinach has a high level of oxalates, which are known to interfere with calcium absorption. This makes the bioavailability of calcium in spinach quite low. When you eat spinach, it is estimated that between 5-25% of it is actually absorbed.
What happens when you cook it? The oxalates are broken down. This results in better absorption. But when you do cook it, other nutrients are broken down (like folate and Vitamin C). So maybe eat it both raw and cooked for the best overall nutrition. I like my spinach raw!
The easiest way to determine the bioavailability of any food is to read the label. When you see the RDA (recommended daily allowance), the bioavailability of the food has been considered.
But why are you calculating your calcium? Here is more food for thought:
Observational data from a randomized controlled study from The Journal of Clinical Endocrinology & Metabolism (August 2019), questioned how much calcium consumption contributed to their bone mineral content. After comparing two groups of women over the age of 65 with hip T-scores between -1 and -2.5 (osteopenia and osteoporosis), they concluded that there was no relationship between calcium intake and bone mineral content. The women in the study were followed for six years. During that time, there was no difference in bone loss between the women who consumed the most calcium and those who consumed the least.
The author's conclusion:
Postmenopausal bone loss is unrelated to dietary calcium intake. This suggests that strategies to increase calcium intake are unlikely to impact the prevalence of and morbidity from postmenopausal osteoporosis.
Similar results were also found in a study of premenopausal women who took calcium or Vitamin D supplements. A Cochrane Database Systematic Review from Jan. 2023, concluded the following: Our results do not support the isolated or combined use of calcium and vitamin D supplementation in healthy premenopausal women as a public health intervention to improve BMD in the total hip or lumbar spine, and therefore it is unlikely to have a benefit for the prevention of fractures (vertebral and non-vertebral).
What does all this mean for you and me?
There is more to bone health than calcium and Vitamin D levels, and supplementing may not be enough for you to get the bone changes you need. Getting well-rounded nutrition is going to be your best bet, as nutrients in food are always going to be absorbed better than a pill.
Bone and muscle building take place when two things are present:
1.) sufficient building blocks (all the nutrients from food) and 2.) the stimulus from exercise.
We are learning more about bone health every week. Don't throw the baby out with the bathwater. If you have been prescribed supplements, don't throw them away - have a conversation with your physician. Remember, these studies do not always take into account things like pre-existing conditions, other medications, or your personal activity level. And if you are self-supplementing, again, have a conversation with your physician.
Supplements can interact with your medications. Just because you can buy supplements without a prescription does not mean they are benign.
Stay strong and retire active,
Andrea Trombley PT, DPT
References:
Bristow, S. M., Horne, A. M., Gamble, G. D., Mihov, B., Stewart, A., & Reid, I. R. (2019). Dietary Calcium Intake and Bone Loss Over 6 Years in Osteopenic Postmenopausal Women. The Journal of clinical endocrinology and metabolism, 104(8), 3576–3584. https://doi.org/10.1210/jc.2019-00111
Harvard School of Public Health. The Nutrition Source. Calcium. https://www.hsph.harvard.edu/nutritionsource/calcium/#:~:text=*Bioavailability%20of%20calcium&text=The%20amount%20of%20calcium%20listed,is%20called%20%E2%80%9Ccalcium%20bioavailablity.%E2%80%9D
Méndez-Sánchez, L., Clark, P., Winzenberg, T. M., Tugwell, P., Correa-Burrows, P., & Costello, R. (2023). Calcium and vitamin D for increasing bone mineral density in premenopausal women. The Cochrane Database of systematic reviews, 1(1), CD012664. https://doi.org/10.1002/14651858.CD012664.pub2