Did you know that the best source of Vitamin D is none other than the sun? Tweet This! That’s right, enjoying a few minutes of natural sunlight each day can make a big difference in your body’s Vitamin D levels. In today’s blog post we’ll be discussing the many benefits and various sources of Vitamin D. Are you ready to get started?
What is Vitamin D?
- Fat-soluble vitamin (also known as calciferol) required for several cellular functions in the body.
- One primary role of Vitamin D is that its presence is necessary for the absorption and utilization of calcium and phosphorus from the gut, required for the mineralization of bone.
- It is also involved in immune function, hormonal secretion and protection against types of muscle weakness (National Institutes of Health, 2016).
Although low levels of Vitamin D are usually prevalent in populations who suffer from kidney and liver disorders, healthy adults can also suffer from deficiency. Tweet This! Without a sufficient intake of Vitamin D, the body would only absorb 10-15 percent of dietary calcium consumed through foods (Harvard Health, 2007).
What factors affect Vitamin D levels?
Many factors play a role for contributing to Vitamin D deficiency. Biological, behavioral and environmental factors explain why many Americans are not receiving a sufficient amount to meet daily requirements.
- Skin color. The amount of pigment an individual has can affect the amount of Vitamin D their skin absorbs from the sun. Melanin is the pigment responsible for giving our skin, hair and eyes its unique color. Although the pigment occurs in larger amounts in individuals with darker skin tones and offers more protection from UVB rays from sunlight, it also increases the time it takes for the skin to produce Vitamin D compared to fairer skinned individuals exposure (Vitamin D Council, 2018). Individuals with naturally darker skin tones are recommended to have three to five times more exposure to natural sunlight in order to produce the same amount of Vitamin D as those with lighter skin tones (Nair & Maseeh, 2012).
- Age. As we age, our bodies become less efficient in the production of Vitamin D. Tweet This! In addition, calcium absorption rates in the GI tract are also naturally lessened in adults after age 65. This reduction leads to a susceptible population for developing osteoporosis.
- Weight. Overweight or obese individuals may also require additional amounts of Vitamin D to prevent deficiency. Studies have reported lower serum levels of Vitamin D in obese individuals compared to those with normal weights. Some researchers believe excessive presence of subcutaneous fat could potentially sequester Vitamin D in fatty tissues, therefore reducing its bioavailability (Nair & Maseeh, 2012).
- Gastrointestinal (G.I.) Issues. Because it is fat soluble, Vitamin D requires the presence of fat in the lumen in order to be utilized in the body. Those who suffer from G.I. issues that interfere with the absorption of fat, such as cystic fibrosis and Crohn’s disease, can be at risk for deficiency.
- Seasonal Changes or Where You Live. Those who live further from the equator are exposed to smaller amounts of UVB rays than those who live closer to the equator. The same occurs for those who experience longer or harsher winters, as opposed to those in warmer climates.
What are good sources of Vitamin D?
Natural sunlight does not directly provide Vitamin D to the body, rather it stimulates bare skin cells to produce a precursor in large amounts when exposed to UV rays by a series of reactions in the liver and kidneys, resulting in the active form.
Experts say most individuals need approximately 15 minutes of sunlight per day to receive enough exposure to naturally produce an adequate amount of Vitamin D. Various factors including skin tone, time of day or year, and where you live affect and may reduce the amount synthesized by skin, and therefore require more sunlight exposure (Vitamin D Council, 2018). Attention is required to balance exposure to sunlight to be sufficient, without overexposure which may increase risk of cell damage.
There are tactics you can practice to help minimize the risk of cell damage, including:
- Using sunscreen that blocks both UVA and UVB rays when you plan to stay in the sun for longer than the recommended time.
- Seek shade after getting a moderate amount of sun.
Vitamin D intake in very small amounts can be obtained through eating a variety of foods like salmon, tuna, egg yolks and some mushrooms. In effort to combat deficiency and aid in the eradication of rickets (softening and weakening of bones in children), public health officials created a program to urge manufacturers to fortify foods like milk, orange juice, and cereals with Vitamin D to increase nutrient levels (Institutes of Medicine, 2003).
If you pay close attention when purchasing these types of foods, you may notice that labels (or packaging) often call out the addition of Vitamin D. Despite the public health efforts, Vitamin D deficiency remains a public health issue. So, it’s important to keep in mind that relying on diet alone may not provide sufficient daily amounts for every nutrient your body needs for optimal functioning.
Supplements are a great way to obtain the necessary amount per day your body needs for optimal functioning. The FDA recommended daily amount of Vitamin D for adults is 20 mcg (800 IU). Before incorporating a supplement in your routine, consult with your doctor to discover your current Vitamin D serum level and determine if it is safe for you begin supplementation. Some medical conditions and medications may prevent individuals from taking high doses of Vitamin D.
How do you incorporate appropriate doses of Vitamin D into your healthy lifestyle? Whether its sunlight or supplements, what most important is that your body receives the proper supplementation it needs.
- Gallagher, J. C. (2013). Vitamin D and Aging. Endocrinology and Metabolism Clinics of North America, 42(2), 319–332.
- Harvard Health (2007). Vitamin D and your health: Breaking old rules, raising new hopes.
- Institute of Medicine (2003). Dietary Reference Intakes: Guiding Principles for Nutrition Labeling and Fortification. Washington, DC: The National Academies Press.
- Nair, R., & Maseeh, A. (2012). Vitamin D: The “sunshine” vitamin. Journal of Pharmacology & Pharmacotherapeutics, 3(2), 118–126.
- National Institutes of Health (2016). Vitamin D: Fact Sheet for Health Professionals
- Vitamin D Council (2018). How do I get the vitamin D my body needs?