Vegan Nutrition with Dina Aronson, M.S. R.D.
Dina Aronson, MS, RD is a vegan dietitian whose specialties include chronic disease prevention, vegetarian/vegan nutrition, and lifestyle management. She is the founder and director of VeganRD.com, a nutrition consulting company. Active in many vegetarian nutrition organizations, Dina was the recipient of the American Dietetic Association's Recognized Young Dietitian of the Year Award in 2002.
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I am a new vegan and still learning about what I should pay attention to in my diet for optimum nutrition. Both my grandmother and mother have severe osteoporosis. I have heard that dairy does not protect against osteoporosis, it actually contributes to it. Is this true? As a vegan what can I do to make my diet bone healthy and avoid osteoporosis in my later years?
Given that osteoporosis runs in your family, it is understandable that you are concerned about your own risk.
Many people think that osteoporosis is about how much calcium you consume. Calcium is definitely important, but it is only one piece of the puzzle. There are several components to optimal bone health:
- EXERCISE. There is no question that weight-bearing exercise makes a tremendous impact on bone density. And it is never too late to start! Studies have shown benefit to bone when folks well into their 70's take up activities like lifting light weights. And such exercises have even shown improvements in strength and balance in people in their 80's and 90's. While swimming and bicycling are wonderful cardiovascular exercises, they are not enough to impact bone density. Make sure your regular exercise routine involves bone-strengthening activities such as strength/weight training (work with a certified trainer to be sure your technique is correct and to prevent injury), jumping rope, walking or jogging, yoga, pilates, aeorobics, kick-boxing, etc.
- RETAIN THE CALCIUM ALREADY IN YOUR BODY THROUGH A HEALTHY DIET: It has been argued that losing calcium is a bigger problem than not getting enough. In other words, consuming a ton of calcium will do little good if it doesn't go to the bone, where it is needed. To retain calcium in the body, it is important to optimize your total mineral intake (the body is constantly keeping the delicate balance of all minerals in check), and to be sure you're getting enough of other nutrients, such as vitamin D, which assists in the absorption of calcium (see "calcium retainers" below). It is also important to limit or avoid the "calcium wasters" (see below).
- ENJOY THE GREAT OUTDOORS: Maybe it's the vitamin D from the sun; maybe it's that we're inspired to move more when we're outside. It's probably both. Whatever the reasons, people who spend more time outside have better bone health. Expose your arms and legs (weather permitting) to the sun for about 10 minutes a day if possible. Any longer may increase the risk of skin cancer, so be careful about sun exposure. And take that walk!
It is definitely important to consume enough calcium. (See below for how many milligrams you need per day). Here's a little science to help you understand what's going on: The pH of your blood needs to be tightly controlled in order for you to keep on living, and calcium is one of the many components that directly affects blood pH. So the calcium in your blood has to stay within a tight range. If the calcium level in your blood drops, your body will turn to its reserves—the calcium in your bones—in order to keep the blood calcium levels up. If you consume enough calcium every day, the blood will get what it needs from the calcium in your food, not your bones. The best plant sources of calcium are low-oxalate green leafy vegetables (see information on oxalate below). These include collard greens, mustard greens, bok choy, turnip greens and kale. The calcium from these foods is absorbed better by the body than the calcium from cow's milk! Other good plant sources of calcium include pinto beans, white beans, broccoli, cabbage, sesame seeds, almonds, oranges, figs, tofu, and tempeh. Most nuts, seeds, and dried fruits not in this list are still fair sources of calcium. Finally, fortified soy, nut, and rice milks, fortified soy yogurt, fortified orange juice, fortified cereals, and other fortified foods are suitable options. A calcium supplement provides calcium but is not the best option. Getting calcium from whole plant foods is better because bundled with that calcium in healthy foods is a heap of other health-supporting nutrients. If you feel you need a calcium supplement, discuss this option with a doctor or dietitian specializing in vegan diets.
Potassium and magnesium are particularly important to bone health. Best sources of potassium—fruits and vegetables! In fact, studies show a positive relationship between fruit and vegetable consumption and bone health. The best sources of magnesium are whole grains, beans, nuts, and seeds. Vitamin K is another nutrient known for its important role in bone health. The best sources of vitamin K are leafy green vegetables. As if we need even more reasons to base our diets on whole plant foods!
Vitamin D is essential for optimal bone health but it's tough to get enough. In nature, you'll find vitamin D in fish, some mushrooms, and from the sun. In the modern food supply, you'll find vitamin D added to a slew of foods including milk (cow, soy, rice, nut, etc), cereals, nutrition bars, soy yogurt, orange juice, some faux meats, and other fortified foods (the label tells you if vitamin D is added). You can also get D from supplements. I recommend that all people take a vitamin D supplement; the current recommended intake level may be too low. Vitamin D2 is usually vegan and D3 is usually not. (There are exceptions.) D3 is better absorbed, but most of the D2 is still absorbed. I recommend 1000 IU per day of vitamin D2 for healthy vegans.
Other notable nutrients that play a role in bone health include boron (found in avocadoes and nuts), copper (found in whole grains and legumes), fluoride (be sure that your drinking water is fluoridated), iron (found in thousands of whole plant foods, but highest amounts in leafy greens, soy beans, and most legumes), manganese (found in legumes), phosphorous (found in whole grains and other foods; note that too much phosphorus, from soft drinks for example, may be detrimental to calcium absorption), vitamin C (found in most fruits and vegetables), and zinc (found in whole grains and nuts and seeds). Do you see a pattern here?
To optimize the body's use of the calcium you're getting in your diet, avoid these potential "wasters." First, certain foods cause your body to excrete, or waste, calcium. Protein, particularly animal protein, wastes calcium. Sodium in high quantities also causes the body to lose calcium, so watch your salt and processed food intake. Second, high intakes of certain food components limit the absorption of calcium, for example oxalate, which is found in some leafy green vegetables like swiss chard and spinach and other foods (this is not to say you need to avoid oxalates; they are still healthy but point to the need to get a large variety of calcium-rich foods). Third, a poor diet of processed foods, refined foods, junk foods, and the like do no good for your calcium status. You can eat this way and still be a vegan, but there is no health benefit to eating this way.
So what is the key to optimal bone health? The key is maximizing weight-bearing exercise, maximizing your intake of calcium and other bone-supporting nutrients from healthful plant foods, while minimizing the things that cause the body to waste or not absorb calcium.
To address the dairy issue: A possible reason for the idea that dairy contributes to osteoporosis is the fact that countries that consume the highest levels of dairy products have the highest rates of osteoporosis. Furthermore, it is clear that millions of people in the world eat no dairy products and enjoy excellent bone health. There is no question that dairy is an optional, unnecessary food for humans, and that there is no nutrient in dairy that you can't get from other sources. But is dairy harmful to bones? It is very difficult to isolate dairy as just one factor in the whole bone health equation; there are so many nutritional, genetic, and lifestyle factors that play a role in bone health. There is no clear or profound benefit of obtaining calcium from dairy over calcium from other food sources or supplements. Some studies have shown a slight benefit (though some question these because the vast majority of these studies are funded by dairy organizations), while other studies show no benefit or even a slight risk of fracture (such as in the Harvard Nurses' Health Study). Bottom line? Dairy is not the insurance policy against osteoporosis that many people think it is, nor is it the cause of all of our bone woes. The reality is much more complex.
Recommended Daily Intakes of Calcium (milligrams per day) According to the USDA:
(Calcium requirements are not increased for pregnancy or lactation.)
- Infants up to 6 months: 210
- Infants 7-12 months: 270
- Children 1-3: 500
- Children 4-8: 800
- Males and Females 9-18: 1300
- Males and Females 19-50: 1000
- Males and Females 51 and up: 1200
Note: the upper limit for safety is 2500 milligrams. Please make sure that the calcium in your diet and supplements does not exceed 2500 milligrams.
Given your high risk, please get regular bone density checks and consult with a holistic medical professional for other ways you can keep your bones healthy.