Q:I eat and drink a lot of milk products mostly because I want to be sure I get enough calcium for healthy bones. Unfortunately, I have asthma and a lot of digestive distress, and I've been wondering whether dairy is part of the problem. If I find I'm reacting to dairy products and feel better not eating them, how can I get enough calcium to protect my bone health? -Janet K., Toledo, Ohio
A: The idea that we have to consume a lot of cow's milk for strong bones is deeply ingrained in our society, but it's based mostly on a successful PR strategy by the dairy industry rather than scientific fact. Believe it or not, anthropologists know that people in hunter-gatherer societies who didn't consume milk had much stronger, healthier bones than people from agrarian societies who did.
It's true that milk is high in calcium, and 99 percent of the calcium found in the average adult body resides in our bones. But the long-held belief that we need plenty of calcium to prevent osteoporosis-a disease characterized by porous and fragile bones-isn't asaccurate as you'd think. Numerous studies have found no association between high calcium intake and lower fracture risk.
Calcium Sources vs. Inhibitors
The truth is: we can get the calcium we need from nondairy foods. Good sources of calcium include dark-green vegetables such as broccoli, broccoli rabe, garden cress, collard greens, turnip greens, kale, bok choy, and grape leaves; white beans; sesame seeds, hazelnuts, and almonds; and wild salmon and sardines.
In addition to consuming enough calcium, we need to help our bodies properly absorb and utilize that calcium. And that means reducing our intake of calcium inhibitors, which adversely affect calcium metabolism and degradebone health. Common calcium inhibitors include excess sodium in the diet from too many processed foods; soft drinks or too much sugar in the diet; excessive fiber and phytate from grains such as wheat; high amounts of caffeine from coffee, tea, and soft drinks; excessive alcohol consumption; and cigarette smoking.
Our focus on calcium also causes many of us to overlook other foods and nutrients that are just as important for bone health, including:
Fruits and vegetables-Fruits and vegetables contain an array of vitamins, minerals, antioxidants, and alkaline salts, some or all of which can have a beneficial effect on bones. Studies have shown that higher fruit and vegetable consumption is associated with beneficial effects on bone density in elderly men and women, although the exact components that may give this benefit are still to be clarified.
Onions-Studies show that onions can help increase bone density and may be of special benefit to women of menopausal age who are experiencing loss of bone density. Research suggests that women who have passed the age of menopause may be able to lower their risk of hip fracture through frequent consumption of onions.
Protein-Adequate dietary protein is essential for optimal bone mass gain during childhood and adolescence, as well as preserving bone mass as we grow older. Insufficient protein intake is common in the elderly, and is more severe in hip fracture patients than in the general population. Lack of protein also robs muscle mass and strength, which heightens the risk of falls and fractures and contributes to poor recovery in patients who have had a fracture. Good animal protein sources include red meat, poultry, fish, and eggs; vegetarian sources include legumes, nuts, and seeds.
Vitamin D-Known as the sunshine vitamin because it's made in our skin after exposure to the sun's ultraviolet B rays, vitamin D plays a key role in assisting calcium absorption and ensuring the correct renewal and mineralization of bone tissue. Maintaina sufficient D supply through adequate, safe, nonpeak exposure to the sun, regularly eating fatty fish, or taking vitamin D supplements.
Vitamin K-Vitamin K is also required for the proper mineralization of bone. Some evidence suggests that low vitamin K levels lead to low bone density and increased risk of fracture in the elderly. Vitamin K1 is abundant in leafy green vegetables such as lettuce, cabbage, kale, broccoli, and liver; vitamin K2, deemed essential for bone health, is best obtained from supplements.
Magnesium-Magnesium plays an important role in forming bone mineral. Particularly good food sources include dark leafy greens, nuts, seeds, beans, avocados, and fish.
Zinc-This mineral is required for bone tissue renewal and mineralization. Severe deficiency contributes to impaired bone growth in children, and milder degrees of zinc deficiency have been reported in the elderly and could potentially contribute to poor bone status. Red meat, poultry, and pumpkin seeds are good sources of zinc.
To put it simply, we need a whole-foods diet rich in nutrients across the board to promote healthy bones. And don't forget about the importance of moving your body. Weight-bearing exercise, such as walking, running, strength training, and dancing, helps build bone mass and strength in the young, maintains bone density in adults, and slows bone loss in the elderly.
Bad to the Bone
Avoid these bone health robbers:
- Excess sodium
- Soft drinks
- Too much sugar
- Excessive fiber and phytate from grains
- High amounts of caffeine
- Excessive alcohol consumption
- Cigarette smoking
Trouble with Milk?
Some people who have trouble digesting milk have lactose intolerance, a condition in which the body is deficient in lactase, the enzyme necessary to digest lactose milk sugar. When lactose isn't broken down, it passes into the large intestine, causing gas, diarrhea, and other unpleasant symptoms. These issues can often be avoided by consuming lactose-free dairy products, or by taking a Lactaid digestive enzyme.
Dairy allergies, on the other hand, are an immune response to a protein found in dairy products, rather than an enzyme deficiency. If you have an allergy to cow's milk, eating dairy products-even if they're lactose-free-will continue to cause health problems, including diarrhea and abdominal cramping. But symptoms aren't limited to digestive distress. Dairy allergies can also cause skin rashes, nasal congestion, joint aches, asthma, and earaches.
Determining whether you have a problem with dairy isn't always easy. Milk products can cause "slow" reactions, which means symptoms develop over time-from several hours to days later. Or they can provoke symptoms quickly, within seconds to hours after consuming dairy. Either way, if you avoid cow's milk products altogether, your symptoms should improve.
It's easy to find milk alternatives made from almonds, cashews, coconut, hazelnuts, flax, rice, or soy in natural food stores. Beware, though: All of these products have been known to cause allergic responses in some people, so you may have to try out a few before you find one that works for you.