Q: My doctor drew my vitamin D level and is recommending that I take 50,000 units of vitamin D once a week. That sounds like a lot to me. At 58 years of age, how important is vitamin D?
A: Vitamin D, the “sunshine vitamin,” is a whole lot more important to our health than most folks realize. It’s the hottest vitamin under study these days, with new studies coming out every month showing how supplemental vitamin D can protect against osteoporosis, heart disease, ovarian cancer, colon cancer, kidney cancer, prostate cancer, Parkinson’s disease, multiple sclerosis, dementia, fatigue, psoriasis, tuberculosis and colds/flu. Did you ever consider that colds and flu are worst in the winter, the time of year when sunlight and vitamin D levels are at their lowest?
What we know is that there are a lot of health conditions that vitamin D may help, yet the prevalence of folks with low levels of vitamin D is about 50 percent. A normal vitamin D level (measured as a 25-hydroxy vitamin D level) is between 30 and 100, with a target of at least 50-60 for optimal disease prevention. A toxic level of vitamin D is greater than 200, and it’s really difficult to exceed that limit with daily or weekly vitamin D supplementation. The U.S. RDA recommends a conservative dosing of 400-600 units of vitamin D per day, failing to consider that individual vitamin D levels may still show deficiency. I’ve had several patients, including a pilot and a software engineer with undetectable vitamin D levels!
Milk contains only 100 units of vitamin D per eight ounce glass. If you live north of the latitude line of Atlanta, no amount of sunshine in the winter can raise your vitamin D level. A rough rule of thumb is that every 100 units of vitamin D taken daily will raise your vitamin D blood level by one. With supplementation, I recommend monitoring the vitamin D and calcium levels every three months.
Q: My father died a number of years ago from a condition called “polyarteritis nodosa.” I’ve never quite understood what it is, other than it caused him to suffer a heart attack. Can you explain it?
A: “Polyarteritis nodosa” (PAN) is a rare form of vasculitis, an inflammation of the muscular walls of arteries. That’s pretty serious, because the blood flow supplied by those arteries is greatly reduced. In this particular form of vasculitis, small and medium-sized blood vessels are not only damaged from inflammation, but they can develop weaknesses in their walls leading to aneurysms and sudden blood vessel rupture.
Polyarteritis nodosa means “many”(poly); “arteries”(arter); “with inflammation”(itis); “occurring at nodes or branch points” (nodosa). When the disease was first described in 1866, mainly blood vessels at branch points seemed to be affected. That’s not really true. Why this blood vessel inflammation occurs is unknown. For some reason, the person’s immune system begins attacking its own blood vessel walls as though it were a foreign invader. We call this an “autoimmune reaction” — the same sort of inappropriate attack that causes rheumatoid arthritis, lupus, and hypothyroidism. PAN is not hereditary. Viruses (esp. hepatitis B) or bacterial infection may trigger it by inducing a hypersentivity reaction.
Making the diagnosis of PAN can be pretty tough. There isn’t any blood test that we can perform. Symptoms are often vague, particularly since vasculitis can involve arteries in many areas of the body. The organs most often affected include the kidneys, intestines, brain, muscles and heart. The most common cause of death is due to kidney damage which leads to severe high blood pressure and kidney shutdown. A ruptured aneurysm may also cause death.
There’s also tissue and organ damage due to the poor blood flow to many organs and muscles. The only way to diagnose PAN for certain is by performing a biopsy of the involved tissue when vasculitis is suspected.
Treatment of PAN is often difficult because so many blood vessels and organs are affected. The goal of treatment is to suppress an overactive immune system that’s attacking itself. Steroids are the first step in treatment. When that fails, more powerful immune-suppressing drugs like methotrexate and Cytoxan are used. Without treatment, almost all who have PAN die within 2-5 years. With early diagnosis and treatment, 10-year survival can be as high as 90 percent.