Here in the south, we’ve been enjoying a steady supply of sunshine over the past few weeks and I have been soaking it up. Having been born and raised in the Northeast, this is a very pleasant change for me. But the summer sun is about a lot more than just getting a tan; sunlight is the best source of vitamin D, a nutrient that offers a host of benefits. Shown to improve everything from depression to heart health, getting adequate vitamin D levels should definitely be a priority for you. But, for the athletes and fitness enthusiasts out there, vitamin D has a special interest.
Previous research has found that obese people tend to have a vitamin D deficiency but the link wasn’t fully understood. A new study, however, has shed some light on how vitamin D can affect your weight loss and healthy living efforts.
Things really started when researchers realized that the hypothalamus – a region of the brain that is responsible for weight and blood glucose levels – comes fully equipped with vitamin D receptors. Logically, this would explain the link between low vitamin D and obesity. However, more research was needed to be sure.
In an effort to solidify, and understand, this connection researcher experimented with the effects of vitamin D supplementation on obese rats. Over the course of the study, one group have vitamin D injected directly into their hypothalamus, another was given a vitamin D drink and another was given a placebo. All of the groups had their fasting glucose levels taken and then were given a shot of pure sugar to test their insulin reactions.
Both groups that had been given vitamin D were highly sensitive to the release of insulin and their blood sugar levels were quickly returned to normal levels.
Another separate, but related, study gave a group of rats vitamin D supplements for 28 days and observed their eating patterns. In that time, the vitamin D group ate an amazing three times less food than the control group. The vitamin D rats also lost nearly a quarter of their body weight, while the control group lost no weight at all.
What Does It All Mean?
Okay, so how can you use this information in a practical way?
First, these findings show that maintaining adequate levels of vitamin D can help you to stay sensitive to insulin. Along with acting to keep your blood sugar levels balanced and healthy, insulin sensitivity will make sure that your body does not store fat excessively and will ensure that your muscles get the nutrients that they need to grow.
The second study, regarding long-term use of vitamin D, also suggests some interesting effects of the supplement. The rats that lost weight did not experience any change in their metabolism; they simply were not hungry. This is likely a result of insulin’s role in satiety – or feelings of hunger. When people are insulin resistant, their brain is not listening to signals from insulin saying that they have all the nutrients they need. And so they always feel hungry.
Since, as these studies show, vitamin D supplementation has the ability to increase sensitivity to insulin it is logical to assume that feelings of hunger would return to normal levels.
But should you start supplementing? That’s hard to say. These studies, while promising, were performed on rats. No human studies have recreated these results so the exact dosage is not known.
That being said, if you do decide to give it a try make sure you take vitamin D3 since this is the most bioavailable form of the vitamin. Of course, you should always talk to your doctor before beginning any supplementation.
Have you benefited from vitamin D supplements when it comes to weight loss and blood sugar levels? Please share your experience with us in the comments.