I have arthritis and am developing knobs on my bones. Should I reduce my calcium intake? Also, what are good sources of calcium if you are lactose intolerant?
Actually, the swollen joints that result from arthritis aren't caused by consuming too much calcium.
Osteoarthritis, the most common type arthritis in older people, starts when cartilage -- the tissue that pads the bones when they form a joint -- begins to wear away. The bones themselves start to rub against each other, and that's what causes the inflammation.
As the disease progresses, bone spurs can form in the joints, but, again, that's not due to excess calcium in the diet. If you do consume too much calcium, the body simply excretes it. In fact, some research suggests that calcium deposits are just as likely to form in people with low calcium in the bloodstream as those with ample calcium.
Even the Arthritis Foundation encourages everyone to be sure they get enough calcium as a way to promote bone health. How much is enough? It depends on how old you are. Adolescents between ages 9 and 18 should get 1,300 milligrams a day. Adults up to age 50 should get 1,000 milligrams, and those over age 50 should get 1,200 milligrams a day.
Dairy sources are often recommended to help you get enough calcium, because they contain a concentrated source of calcium that's about as absorbable in the body as any calcium can be. Vitamin D helps the body absorb calcium, so check the label to be sure your calcium source also contains vitamin D.
If you're lactose intolerant, you could try consuming smaller amounts of dairy products (for example, a cup or less of milk) at a time. If that still gives you some gastrointestinal distress, other good sources of calcium include:
- Calcium-fortified orange juice or soy milk. One cup can contain as much as 350 milligrams of calcium. Check the Nutrition Facts label -- the percentage of calcium listed is based on a Daily Value of 1,000 milligrams.
- Calcium-fortified cereal, bread. The amount of calcium varies greatly; again, check the label.
- Dark green leafy vegetables, such as spinach, broccoli and bok choy. A cup of cooked frozen spinach contains 290 milligrams of calcium, but, unfortunately, it also contains oxalic acid, which reduces the body's ability to absorb the mineral.
- Calcium supplements. Take no more than 500 milligrams at a time; your body can't absorb more. Again, be sure they also contain vitamin D.
Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or firstname.lastname@example.org.
Editor: This column was reviewed by Lydia Medeiros, food safety specialist for Ohio State University Extension and professor in the Department of Human Nutrition in the College of Education and Human Ecology.