Reappraising Vitamin D and Calcium Supplementation


Recently the U.S. Preventive Services Task Force (USPSTF) issued a recommendation against routine daily supplementation with vitamin D and calcium in most circumstances. They conclude that there is adequate evidence demonstrating the taking 400 units of vitamin D and 1,000 mg of calcium does not prevent fractures in postmenopausal women. In addition, they note that the aforementioned supplementation does cause an increase in kidney stones and, therefore, is associated with harm.

It is unclear whether higher doses of vitamin D and calcium prevent fractures in men and postmenopausal women. Oddly, vitamin D supplementation is effective in preventing falls in community-dwelling adults aged 65 or older who are at risk for falls. The USPSTF does recommend vitamin D for this group.

Although the routine use of vitamin D and calcium supplements have been called into question the need for adequate levels of vitamin D in the body remains a constant. Those who lack enough vitamin D suffer from inadequate bone formation and, in addition, lack the beneficial effects of vitamin D on muscle strength and balance.

Obtaining vitamin D from dietary sources is best, just as we find that all vitamins are most effective when obtained from dietary sources. Good sources of vitamin D include: fatty fish and fortified foods, such as milk, yogurt and orange juice.

For individuals at risk for vitamin D deficiency supplementation is essential. This group would include the chronically ill, patients with intestinal malabsorption, pregnant women and those being evaluated for osteoporosis.

For now, the best approach might be to measure vitamin D levels in individuals at risk for vitamin D deficiency, including those mentioned above, older women, and women with risk factors for osteoporosis, and use vitamin D supplementation to bring the levels to normal.

Risk factors for osteoporosis include bone fracture, a family history of fractures or osteoporosis, smoking, excess alcohol consumption, malabsorption, the use of certain medications, sedentary life style and small body frame.


Lyme Disease: The Basics of Prevention

Lyme disease is a tick-borne illness with a peak incidence in the eastern United States during the summer months of June, July and August. The late manifestations, such as arthritis, can appear at any time during the year. It is most common in the northeast and mid-Atlantic states (from Maine to Virginia), the Midwest (Minnesota, Wisconsin and Michigan) and on the west coast in northern California.

The ticks are carried by mice and deer and are more likely to infect when they are quite small (the size of a poppy seed.) When the ticks change and become larger they are less likely to transmit infection. Ticks are most commonly found on the underside of low-lying shrubs or grass, particularly between grass and forest. They are not common on well-cut lawns, such as a golf course. A tick can attach to a pet and then attach to a human, thereby transmitting the disease. If the tick is removed before it becomes large (engorged with blood) it is very unlikely to transmit Lyme disease.

If a tick is on the skin, but does not bite it cannot transmit disease. If a tick is removed within 48 hours the risk of transmission is quite small. The risk of transmission in one study where a tick was removed before it was engorged in an area where 15% of ticks carried Lyme disease was only 1%.

The best way to remove a tick is with tweezers or your fingers covered with some protection, such as a disposable rubber glove. It is important not to crush the tick. After removing the tick wash the area and your hands with soap and water.

Taking the antibiotic doxycycline to prevent Lyme disease makes sense only under certain conditions: that the tick is a deer tick; that the tick has been attached for more than 36 hours; that doxycycline can be started within 72 hours after the tick has been removed; that the tick bite has occurred in areas of the US where Lyme disease is common; and that the person does not have a contraindication to the use of doxycycline (a tetracycline.)

If a person cannot take doxycycline then no antibiotic should be prescribed as prophylaxis against developing Lyme disease after a suspicious tick bite. Doxycycline is usually given as a single 200 mg dose.
The time between a tick bite and the onset of Lyme disease symptoms is 2 to 3 weeks. The first manifestation is usually a rash. Lyme disease also can cause arthritis, neurological problems, heart conduction abnormalities and other problems. Unfortunately, it takes two weeks for antibodies to appear in the blood making a blood test for Lyme at the time of the tick bite useless.

Causes of Fatigue that Slip Through the Cracks

I consider fatigue caused by sinus and nasal issues to be the most common cause of otherwise unexplained chronic fatigue. I’ll describe the evidence for this opinion later but, for now, let’s consider some medical causes that can be missed.

An interesting study examined the amount of iron in the blood of women who were not anemic. Usually an iron deficiency, if severe enough, causes anemia but this study was limited to patients with mild iron deficiency, enough to be noted when examining the blood specifically for iron stores but not enough to cause anemia.

The distinction is an important one. Prior to this study physicians usually thought that iron deficiency would not cause fatigue if the deficiency was not severe enough to cause anemia. The study went on to measure the level of fatigue before and after iron replenishment. The level of fatigue dropped after the iron stores were returned to normal.

Two points are evident from this study: The lack of anemia does not rule out iron deficiency as a cause of fatigue. Additionally, measuring iron stores as simply the level of iron in the blood is inadequate. The iron stores must be measured as “ferritin” a simple and inexpensive blood test but one not always done when evaluating a person for fatigue.

Occasionally low thyroid causes fatigue despite a normal TSH—the usual screening test for low thyroid. TSH comes from the pituitary and increases in the event of a failing thyroid usually providing the earliest clue that the level of thyroid hormone is inadequate.

Occasionally the pituitary is the problem and although the TSH should be climbing as the thyroid fails, it does not. Checking the actual levels of thyroid hormone (T4 and T3) will pick up a thyroid problem even in the event of pituitary insufficiency.

Sometimes an arthritis disease can cause even in the absence of severe arthritis symptoms. Almost always the severity of the arthritic disease seems quite proportionate to the complaint of fatigue. Occasionally this is not so. A person might have rheumatoid arthritis with minor joint problems but have significant fatigue. Treating the rheumatoid arthritis usually causes substantial reduction of fatigue.

A note of caution: The vast majority of individuals with unexplained fatigue and very minor arthritis symptoms do not have positive blood tests for arthritic diseases. Even when the blood tests turn out positive the blood abnormality is, almost always, at a low level, unrelated to the minor arthritis. In these cases treating the person as if the individual did have a serious arthritis disease does not improve the fatigue. In short, arthritis blood tests in the setting of unexplained fatigue are often a “red herring,” but not always.

Occasionally a person may have unexplained fatigue due to a liver problem in the absence of abnormal screening liver function tests. Usually other screening tests, however, denote inflammation.

As mentioned before, the best screening tests to determine if, what appears to be unexplained fatigue, is actually caused by a medical problem are the erythrocyte sedimentation rate (ESR) and the C-reactive protein. Both of these are elevated by any process that causes inflammation. Usually any medical disease that causes fatigue causes inflammation as well.

The ESR and CRP won’t tell you the cause of the problem but do let you know that there is a problem. The absence of ESR or CRP abnormalities does not mean that the cause of fatigue is not physical. However, when these tests are elevated a physical cause of fatigue becomes much more likely.