Two of the conditions that may be associated with gluten sensitivity (GS) and/or Celiac Disease (CD) are osteoporosis (thinning and weakening of the bones) and osteopenia (softening of the bones.
Bones go through a continuous process of forming and re-forming. For the most part, this slows down as we age—and the bones can become brittle (osteoporosis) or soft (osteopenia). Both may be due to a number of factors and complicating conditions. It’s a long list, but that list includes GS and CD as well as hereditary disorders, endocrine disorders, chronic disease and cancers. Other risk factors include decreased physical activity, using steroids such as prednisone for more than 3 months, deficiency in Vitamin D, calcium and phosphorus, heavy alcohol use, a family history of osteoporosis, having a white or an Asian ethnic background, low body weight and a history of smoking.
There are few symptoms of early osteoporosis or osteopenia—later in the disease, bone pain or tenderness may appear—often in the neck or low back. Unfortunately, the first sign of bone disease is sometimes a fracture or break at the wrist, or in the bones of the spine, the vertebrae. One of the well-known leading causes of osteoporosis is the drop in estrogen that accompanies menopause, though men are at risk for osteoporosis as well. There have been some patients who were diagnosed with previously unknown GS or CD because of their complaints of muscle weakness and bone pain that turned out to be osteoporosis secondary to nutritional deficiencies that have been associated with GS/CD (1,2).
CD and GS put a person at risk for osteoporosis and osteopenia, mainly it appears, because of problems getting adequate levels of calcium and vitamin D, as well as other nutrients(1). The rates are estimated to range to up to 34% of patients with CD—these rates may be similar for GS. There may, however, be additional factors. One line of thinking is that poor absorption of calcium and a vitamin D deficiency may set up what is known as secondary hyperparathyroidism.(1,1,2). The term secondary is used because the parathyroid is affected as a result of GS/CD—in other words, the first problem was GS/CD and the parathyroid condition was the second problem—and that second problem was related to the development of osteoporosis.
The parathyroid glands are located on the thyroid gland which is at the base of your neck. The thyroid gland controls a great deal of your energy and metabolism—all the biochemical reactions going on in every cell of your body. The parathyroid glands are four small areas on the thyroid—these glands regulate calcium (Ca), phosphorus (P) and vitamin D activities. They are about the size of a grain of rice and are actually located behind the thyroid gland. These parathyroid glands secrete a hormone, aptly named parathyroid hormone (PTH) or sometimes parathormone.
The main role of parathyroid hormone is to keep the body’s calcium levels within a very narrow range—too much or too little calcium in the blood and tissues can seriously affect your health, particularly your heart, skeletal muscle and your nervous system. When the calcium levels drop below a certain level, the parathyroid gland begins to produce and secrete PTH. PTH increases the calcium levels in the blood by stimulating the release of calcium from bones. PTH will at the same time increase the absorption of calcium from foods and prevent the kidneys from excreting calcium. PTH works along with vitamin D to increase the absorption of calcium from your foods.
Vitamin D is required to make calcium-binding proteins that allow for this increased absorption from foods. As the calcium levels in the blood are increase, the phosphorus levels (in the form of phosphates) decrease—so as the calcium goes up, the phosphates are reduced. While phosphates don’t appear to directly affect the secretion of PTH, diets high in phosphates—diets with high amounts of meat, for example, can cause increased secretion of PTH.
Calcium (and phosphates) is essentially stored in the bones. So, if a long-term calcium deficiency exists because of dietary deficiencies or malabsorption because of long-term GS, the parathyroid gland may become overactive—grabbing more and more Ca from the bones. A vitamin D deficiency worsens the problem. The eventual result may be osteoporosis.
In a recent study, individuals with osteoporosis were found to be 10 times more likely to have biopsy-proven CD (1). And, in another recent study of 255 postmenopausal women with osteoporosis but without any signs or suspicion of either GS or CD, almost 10% were positive for serum antigliadin antibodies and positive for tissue transglutaminase antibodies (1). This may suggest that GS and CD may be under-diagnosed in postmenopausal women and patients being treated for osteoporosis (1).
What would be the recommendation for people with GC or CD for calcium and vitamin D supplementation? Calcium carbonate (essentially, chalk….no, really!) is the least expensive but is best absorbed with food. As an aside, those antacids that tell you they are a source of calcium….not so much, because they decrease stomach acid—and calcium is best absorbed with higher stomach acid. Calcium citrate or glycinate—and other forms of calcium—can be taken on an empty stomach, but are more expensive.
Talk to your health care professional for specifics—there may be some concern if you are at risk for heart attacks, but 1000-1500 mg of calcium a day is generally recommended. As always, your best source of calcium is in whole foods—and those best sources are spinach, turnip greens, mustard greens, collard greens, sardines, yogurt, goat and cow milk, and blackstrap molasses.
Vitamin D is best gained from 10-15 minutes in afternoon sun 3-4 times a week. If you live in a northern area with little sun during those winter months, the Institute of Medicine suggests that you can safely take 2000IU of vitamin D every day. There is some controversy as to what normal blood levels of vitamin D should be, but most agree that it should at least be greater than 30ng/mL. Food sources of vitamin D are cod liver oil, fish such as salmon, mackerel, tuna and sardines, dairy products, liver and eggs. Vitamin D is a fat/oil-soluble vitamin—so again, watch for the marketing for the vitamin D fortified foods! Orange juice, for example, is mostly water….ever try to mix any oil with water? Yep—you be the judge! The chemist in me is doubtful…..