Since my blogpost about Vitamin D several months ago, I’ve noticed dozens of articles, research studies and even books about the “sunshine” vitamin. It seems to be the new “it” vitamin that everyone’s talking about. Vitamins A, B and C have had their 15 minutes of fame. Apparently, it’s D’s turn and, as my own physician said to me, “it’s hot.”
To find out why, I contacted the leading proponent of Vitamin D, the author of “The Vitamin D Cure,” Dr. James Dowd , a rheumatologist and founder and director of the Arthritis Institute of Michigan. He responded to my questions by email, which I gladly share with you here.
First, why is Vitamin D such a hot topic these days?
Vitamin D is “hot” because relevant clinical studies have only just been published in the last 5-7 years. Prior to that, all the studies were laboratory research done by Ph.Ds. Books like The Vitamin D Cure and The UV Advantage have also rasied public awareness.
Let’s start with an explanation of what happens to a woman’s body in mid-life and why you think Vitamin D can be beneficial.
As we age we lose a number of steroid hormones that help to regulate our metabolism and maintain our physical “plant.” After adolescence our growth hormone levels begin to decline and this decline can accelerate with age. At menopause, women lose estrogen and progesterone for the most part and this loss is abrupt. (Men lose testosterone gradually as they age).
The loss of these hormones leaves us without a building maintenance crew. They’ve all retired but we are still here. Our body begins to feel this loss in the form of declining bone and muscle (lean body mass). This is associated with degenerative bone and joint disease, weakness and weight gain. Everything seems to be falling apart.
We are now exposed to the elements of our lifestyle with no hormonal protection from our unhealthy behaviors. In other words as you come of age you are given control of everything – no more autopilot from hormones.
Vitamin D is a steroid hormone that we have control over and we need it more in the absence of estrogen and androgens and growth hormone. Vitamin D is one of the last members of the “maintenance crew” and one that never has to retire. So it’s essential to make sure that your vitamin D levels are normal through sun and supplement.
So tell us specifically what Vitamin D does for us?
Vitamin D can help to maintain bone and muscle mass, lower your blood pressure, protect you from gum disease and tooth loss, lower your risk of any cancer by more than 50 percent, lower your risk of falling and breaking a bone, improve your mood, reduce your fatigue, and maybe even prolong your life. Along with your cholesterol, blood pressure and BMI, your vitamin D level is a vital sign that you should monitor and optimize.
How do you know if you have enough Vitamin D?
Ask your doctor for a serum 25-hydroxyvitamin D test. Normal blood levels are 35-100ng/mL for optimal health. The ideal is in the middle of this range — between 45ng/mL and 70 ng/mL.
What do you recomend as a daily dosage?
First, take D3, not D2, which is only 1/4 as potent. Dosages vary with weight and depth of deficiency, so one size does not fit all. The bigger you are, the more you need and the lower your level the more you need. (A panel of Vitamin D scientists recommmend a daily intake of 1000-2000 IU/day. Intake of 2000 IU/day is the current upper limit of the National Academy of Sciences, Institute of Medicine, Food and Nutrition Board).
I’ve read that Vitamin D can help fight mid-life weight gain. Is this true?
A high vitamin D and calcium breakfast has been shown to reduce consumption of calories for the remainder of the day. Calcium absorbed as a result of normal vitamin D levels has been shown to inhibit the storage of energy as fat. Vitamin D increases the absorption of phosphorus, which is necessary for ATP production. We believe this is one of the reasons for less fatigue on vitamin D. It has also been shown to improve mood better than light therapy in studies on seasonal affective disorder.
Improved mood and less fatigue/increased energy leads to increased physical activity, which means you’re burning more calories.