Vitamin D has several functions in the body. It helps keep our bones strong and plays important roles in immunity and neuromuscular function. It's also a key regulator of fat and metabolism.
Our skin makes vitamin D when exposed to sunlight. Levels are naturally highest in the summer when days are long and the sun's rays are most intense. Vitamin D deficiency is most common in winter, when days are short and the sun's rays are least intense.
Observational studies show that people with the lowest levels of vitamin D gain more weight, on average, than people with the highest levels. This doesn't mean that low vitamin D levels cause weight gain, but it does show that low levels of vitamin D may predispose people to gain weight more easily.
Evidence is emerging that tests for measuring vitamin D in the body are unreliable and may be influenced by factors like inflammation, which has been shown to decrease levels of vitamin D. Even if testing would produce accurate results, it only tracks a couple of vitamin D metabolites, but more than 50 exist in the body.
Vitamin D supplements don't have the same effect as sun exposure. Sunlight stimulates several different biochemical pathways, and vitamin D production is only one of the beneficial effects. Sunlight also helps regulate our circadian rhythm, which can act as a master control switch for fat metabolism.
To maintain a healthy weight during the holidays, follow these five tips:
# 1 Get daily sun exposure, preferably in the early morning hours, and take 800 to 1200 IU of vitamin D3 daily. Higher doses can carry side effects and so far research studies don't show bigger benefits. Avoid intense sun exposure.
# 2 Exercise regularly, even when you're busy. Prioritize it and make it happen. When you travel, take your athletic shoes along so you can exercise anywhere, even if you only have time for a brisk 30-minute walk.
# 3 Eat protein, healthy fat, and fiber at every meal.
# 4 Minimize your intake of sweets, starches, caffeine, and alcohol.
# 5 Get plenty of sleep and keep a regular schedule as much as you can.
Once the holidays are over, schedule an appointment with your naturopathic doctor to address the environmental aspects of weight gain.
More than 400 chemicals from the environment have been found in human blood and fat tissue and many of them have been linked to weight gain and obesity (as well as diabetes, cardiovascular disease, autoimmune disease, infertility, depression, Alzheimer's disease, and even cancer).
Let your naturopathic doctor tailor a detox program to meet your individual needs and help you achieve your weight loss goals.
Janesick A. and Blumberg B. 2012. Obesogens, stem cells and the developmental programming of obesity. International Journal of Andrology 35(3):437-48.
Leblanc E.S. et al. 2012. Associations between 25-hydroxyvitamin d and weight gain in elderly women. Journal of Women's Health 21(10):1066-73.
Thayer K.A. et al. 2012. Role of Environmental Chemicals in Diabetes and Obesity: A National Toxicology Program Workshop Review. Environmental Health Perspectives 120(6): 779–789.