The first 20 years of life is an important window in time when the body builds more bone than it does remove old bone – a natural process that occurs throughout one’s lifetime. As we age, the process involving bone building starts to slow, and bone mass is lost. Ideally, we need to take advantage of those first twenty years and build strong, healthy bones. After that, race, gender, genes, lifestyle, diet/nutrition, exercise, supplements, and medications all play a part in bone density. For example, after menopause, women are more likely to lose bone mass due to the decline in the hormone, estrogen. And even though male androgen hormones decline at a slower rate as men age, by the age of 65-70, men lose bone mass at the same rate as women. In fact, at the rehabilitation hospital where I work, I see many older men with spine or hip fracture.
Building and maintaining healthy bones is important. Whether you’re a parent looking to make sure your kids build strong, healthy bones or worried about how maintain your own bone mass as you age, this blog post is intended to clear up some nutrition and supplement confusion and to provide nutrition and lifestyle habits geared toward helping build and maintain strong, healthy bones.
So, how do we build healthy bones?
And if we are well past our twenties, how do we keep our bones strong?
It’s no surprise that calcium and vitamin D are essential nutrients for bone health. Calcium provides the building material for strong bones, and vitamin D helps your body absorb the calcium. The following table developed by Institute of Medicine (IOM) lists the recommended daily calcium and vitamin D intake for adults:
Even with all of the research that went into developing this table, the IOM received backlash from other groups scrutinizing this table. Some groups argued that daily values for calcium and vitamin D should be increased, while other groups argued that daily values should be reduced. The truth is, it’s still not very clear as to how much calcium or vitamin D we need to build or maintain bone health.
So if based on this chart, you don’t think that you’re getting enough calcium or vitamin D, there’s no reason to start downing supplements. In fact, excess calcium from supplements can be unhealthy – especially if you have hypertension. If you have hypertension, calcium can build up in your arteries. Add this to arteries already ladened with plaque, and you have further narrowing of your arteries. There is then a potential for plaque to burst from the artery wall, find its way to the heart or brain, and cause a heart attack or stroke. This is why, as a dietitian, I make it my business to know the nutrients in whole foods. Plus, it's better to get as many of your nutrients from whole foods since they are better absorbed by your body versus those from a supplement.
With that said, what are the best food sources of calcium?
Most people assume that dairy is the best source of calcium when actually, it’s not necessarily clear that dairy products are the best source of calcium for most people. I’m not jumping on that dairy-bashing wagon because both calcium and dairy have many positive benefits - They can both help to lower the risk of osteoporosis and colon cancer. But on the flipside, high intakes of calcium and dairy can increase the risk of prostate cancer and possibly even ovarian cancer. Plus, full fat dairy products can be high in saturated fat, while others can be high in retinol (active form of vitamin A), and at high levels, retinol can actually weaken bones. So if you’re not into consuming the USDA recommended 3 servings of dairy per day, don’t be discouraged, just look beyond the dairy aisle for some good sources of calcium. These include:
Vegetables: Collards, Bok Choy, Broccoli, Brussel Sprouts, and Spinach. These are all great sources of vitamin K, which is another important nutrient for bone health (2). Spinach wants to hold onto calcium, so cooking it and adding a little acid, like lemon juice, can help your body better absorb the calcium.
Nuts and Seeds: Almonds, Sesame Seeds, and Chia Seeds
White beans, and Baked beans: These are also full of magnesium, which is also used to make strong bones.
Sardines: These are also loaded with Omega-3 to fight inflammation!
Fortified Soy Milk
When eating calcium rich foods, you’re going to want to make sure that the calcium is absorbed, which is where vitamin D comes into play!
The sun is a great way to get vitamin D.
Our skin cells, with a little sunshine, help our liver and kidneys make vitamin D. Just 10 minutes a day (no sunscreen) with a short sleeve shirt and shorts is all you need. Unfortunately, if you spend winters in the northern U.S., have little exposure to direct sunlight, and if you are very susceptible to sunburn and need to wear sunscreen with an SPF of 8 or more, you will need to actively look to consume foods high in or fortified with vitamin D. I say actively because unless a food is fortified with vitamin D, like dairy, soy, orange juice, or breakfast cereals, there are few foods that contain vitamin D. Foods containing vitamin D include:
Fish: Sockeye Salmon, Mackerel, Halibut, Oysters, canned Tuna Fish
Mushrooms (grown under UV light)
Besides eating foods rich in calcium and vitamin D, there are several lifestyle habits that you can include to build and maintain strong bones. Here are seven great tips:
Exercise! Staying active is a great way to build and maintain strong bones. Research shows that leading an active life can decrease the risk of sustaining fractures in the spine or hip by 30% to 50% (1). It can help to incorporate exercises such as yoga and strength training that incorporate balance to prevent falls, which could lead to fractures. Weight bearing exercises are especially helpful, too. Gravity stresses the bones, and your body responds by reinforcing them. This includes resistance exercises with bands and weights, as well as high impact aerobics such as tennis, soccer, or jogging. Walking and low impact aerobics are also beneficial, but will not build bone as fast as the higher impact aerobics.
Caffeine in Moderation: Drinking more than 4 cups per day can put you at greater risk of breaking a bone. High levels of caffeine can lead to calcium loss through urine.
Don't Go Overdo Protein: Some research shows that high levels of protein from animal sources can raise the acidity level of the body causing calcium to leach from your bones in order to neutralize the acidity.
Drink Responsibly: Heavy drinking (>14 drinks per week for men, and >5 drinks per week for women) can interfere with your production of vitamin D. It can also increase the loss of both calcium and magnesium, needed to keep and make bones strong.
Avoid Excess Vitamin A Supplements: Currently 2300 IU for women and 3,000 IU for men is recommended. Be careful about getting too much retinol (vitamin A) because it can actually weaken bones. In fact, many multivitamin makers have removed much or all retinol and replaced it with beta-carotene, which does not harm bones. If you are taking a supplement that includes the retinol form of vitamin A, be mindful of eating foods that are also fortified with the retinol from of vitamin A, such as milk, energy bars, and breakfast cereals. Together, the retinol form of vitamin A supplements and fortified foods can add up, and weaken bones. It’s best to choose a beta-carotene vitamin A supplement, which has not been linked to weakened bones.
Control Your Salt Intake: During reformation of bone, some calcium will be transported into the bloodstream, after which it will pass through the kidneys. From there, calcium can either get excreted via urine or reabsorbed into the blood stream. Sodium (salt) can increase the chance that calcium will be excreted with urine. If you reduce your sodium intake to one to two grams per day, you will hold onto calcium better. Read food labels, and be mindful that sodium/salt in the foods you eat can be used as a flavoring or as preservatives, like sodium benzoate. Better yet, eat whole foods, and avoid processed foods, salty snacks, and canned or frozen foods with lots of added sodium. When cooking, replace salt with herbs and spices, like onion powder, paprika, garlic, parsley, oregano, thyme, or basil - which will likely make your food taste better anyway!
Quit Smoking: Smokers lose bone faster than nonsmokers. Smoking can interfere with calcium absorption, and lower the amount of estrogen produced. Research shows that men and women who smoke were at a 55% greater risk of breaking a hip than any other bone.
To learn more about how to build and maintain healthy bones, and sustain a lifestyle of healthy eating, contact me at 973.852.3335