Vitamin D helping weight loss has been demonstrated in a number of studies. Recent results show that overweight and obese people given Vitamin D supplements while on a reduced-calorie diet lost more weight than those on the same diet but without the added vitamin.
The success is noted especially in those who are deficient in the vitamin. This deficiency is widespread in North America. It is estimated that 40 percent of adults have low levels of the vitamin in their blood.
How Vitamin D Works
Vitamin D is known as the “sunshine vitamin” because sunlight falling on the skin creates the vitamin in the body. It is also widely available in foods such as eggs, yogurt, milk, orange juice, tuna, salmon and fortified cereals.
Who Benefits from Vitamin D and Weight Loss?
Those with a higher body fat percentage or BMI have been shown to have lower Vitamin D levels. One reason given is that they tend to eat fewer foods with while taking the vitamin. Another is they may not expose their skin to the sun as often, and also they may have lower levels of enzymes that convert the vitamin to its active state. An overweight or obese person needs more of it than a smaller-size person.
All overweight and obese persons should have their Vitamin D levels checked. The weight loss effect are seen in those who are deficient in the vitamin.
Studies on Vitamin D and Weight Loss
An Italian study involved 400 obese and overweight subjects with the deficiency. They were put on a reduced-calorie diet and were divided into three groups. One group received no supplements, one group took 25,000 IU of D, and the third group took 100,000 IU per month. At the end of six months, the two supplement groups lost more weight than the control group.
“The present data indicate that in obese and overweight people with Vitamin D deficiency, supplementation aids weight loss and enhances the beneficial effects of a reduced-calorie diet,” according to Luisella Vigna of the University of Milan, leader of the study.
“However, it is very important to note that the effect of Vitamin D appears to be limited to only those people who are deficient,” notes Dr. Christopher Ochner of Mt. Sinai Hospital in New York, an expert in weight loss, obesity and nutrition.
Vitamin D and Body Weight
Other studies provide more interesting data. One study shows that higher levels of the vitamin in the blood can aid not only in weight loss but in reducing body fat.
A year-long study involved 218 overweight and obese women who were all put on a reduced-calorie diet and an exercise program. One group received Vitamin D supplements, the other got a placebo. The group that received the vitamin lost an average of seven pounds more. Another study showed no weight loss but a decrease in body fat.
Vitamin D can raise levels of serotonin, a neurotransmitter associated with mood, sleep facilitation, and appetite control. Serotonin controls weight by reducing hunger and raising satiety.
It can also raise levels of testosterone which can aid in weight loss. A 2011 study showed that men given the vitamin had greater testosterone levels than a control group, according to a study.
Elevated testosterone levels can reduce body fat, maintain weight loss, and raise the metabolism, which will burn more calories and possibly block the creation of more fat cells. According to the study, “Testosterone supplementation in men decreases fat mass.” However, the mechanism is not known.
The Recommended Daily Allowance for Vitamin D is 600 IU per day. Some studies suggest this should be raised to 32 – 36 IU per pound a day.
Benefits of Vitamin D
It is very important to have adequate levels of Vitamin D in the blood. There are many benefits beyond weight loss. Maintaining the health of teeth and bones is well known. Other benefits include:
- It supports the immune and nervous systems.
- It helps diabetes management by regulating insulin levels. An inverse relationship between type 2 diabetes and Vitamin D levels has been shown in studies.
- It helps lung function and heart health
- Lack of Vitamin D can cause osteomalacia (soft bones) or osteoporosis, the common bone disease in post-menopausal women
- In children, a reduced risk of influenza A has been noted.
- Low Vitamin D levels are associated with an elevated risk of allergic diseases, including asthma, eczema, and atopic dermatitis in children.
- It has been shown to lower the risk of gestational diabetes, preeclampsia, the necessity of a C-section and bacterial vaginosis during pregnancy
- The possibility of benefits in cancer treatment has been studied. It may slow the progression of cancer by slowing down the growth of blood vessels in tumors.
- Vitamin D deficiency has also been studied as possibly raising the risk of multiple sclerosis, Alzheimer’s disease, autism, swine flu, high blood pressure, rheumatoid arthritis, and more. But more studies to confirm these links must be done.
Side Effects of Vitamin D
Too much Vitamin D presents health problems. The upper limit for safe consumption is recommended to be 4000 IU per day. However, up to 10,000 IU will probably not cause side effects.
Symptoms of overdose are vomiting, diarrhea, constipation, headaches, nausea, metallic taste, dry mouth, and loss of appetite. Also, over-calcification of the blood vessels, bones, heart, lungs and kidneys can occur.
How to Use Vitamin D
Using large doses of any vitamin or supplement should be approved by a physician before the regimen begins.
- Blood levels of Vitamin D should be determined by a physician
- Sunshine up to 10 minutes per day is recommended
- Foods suggested are eggs tuna, salmon, mackerel, liver, and Vitamin D-fortified foods
- Vitamin D3 is preferred over D2
- It should be taken with the largest meal of the day since it is a fat-soluble vitamin, meaning that it needs fat to be absorbed into the body.
- Vitamin D is not always safe to take with other medications. Some examples are water pills, antacids, and Lipitor. This should be determined by a physician or pharmacist.
Studies indicate that supplementing a low-calorie diet and exercise plan with Vitamin D can be helpful. However, this has been shown to be beneficial only in obese and overweight people. In men, adding the vitamin can decrease fat tissue. However, there are side effects as noted, some serious and others minor.
There are many other health benefits of taking the supplement. What is known is that anyone contemplating adding the vitamin to a weight loss plan should visit his or her physician for determining blood levels, checking for compatibility with other drugs, and medical advice.