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BY: Breanna Katz Staab
Extension Assistant Nutrition Agent
Opelousas Extension Office

Vitamin D
Why do dietitians and nutritionists encourage a balanced diet of fruits, vegetables, grains, protein and dairy (or sources of calcium for those who cannot consume dairy?). “Well it’s good for you!” is the common response, but why is it good for you? All foods are made up of large nutrients, called macronutrients. These are fats, proteins, and carbohydrates. All foods are also made up of small nutrients, called micronutrients. These are vitamins and minerals that are integral parts of your body’s metabolism, which is the ability to break down food and use those macro- and micronutrients to keep your body operating in an optimal state. What happens when you don’t consume enough of these vitamins and minerals, and you develop a deficiency? In essence, your body can’t function the way it’s supposed to and some part of your body will suffer.

According to the National Institutes of Health, almost 1 in 4 US adults are vitamin D deficient. Many people deficient in vitamin D are asymptomatic for a time, however there are common signs that get overlooked that are indicative of a vitamin D deficiency. Common signs include:

  • Fatigue
  • Poor sleep
  • Bone pain or achiness
  • Depression
  • Hair loss
  • Muscle weakness
  • Loss of appetite
  • Poor immune system

What is Vitamin D? Vitamin D is a fat-soluble vitamin, meaning that it needs to be consumed with a source of fat to be absorbed, and aids in absorption of calcium and phosphorous – the building blocks of bones. Vitamin D also plays a big role in your immune system and cardiovascular, neural, and endocrine health. Your endocrine system controls the release of hormones, which impacts growth and development, reproduction, and metabolism. Vitamin D also plays a critical role in blood sugar control and increases insulin sensitivity (this is a great thing!). This incredible vitamin also regulates more of the human genome than any other single nutrient! It’s no wonder that a deficiency could lead to feeling unwell!

Sources of vitamin D:
You can consume vitamin D through food or through sunlight!

Vitamin D is the only vitamin your body can synthesize through exposure to sunlight – that’s why it’s called the sunshine vitamin! On average, 15 minutes of sunlight a day without sunscreen is enough to stimulate production of vitamin D. If you have darker skin, you will need to stay in the sunlight a little longer to achieve the same results.

If you don’t spend a lot of time in the sun, there are some dietary options to get your vitamin D. First, the recommended vitamin D per day is 600 IUs or 15mcg per day. 

  • Salmon is an excellent source of vitamin D! A 100g or 3.5oz serving contains over 500 IUs of vitamin D, or about 83% of your daily requirement.
  • Rainbow trout contains about 640 IUs in a 3oz serving, or about 100% of your daily requirement.
  • A 3.5oz serving of canned tuna has about 270 IUs, or about 45%.
  • A 3oz serving of portabella mushrooms will give you about 320 IUs, or about 53% of your daily requirement. Mushrooms are the only vegetarian source of vitamin D, but please note – not all mushrooms contain vitamin D. Only mushrooms grown outdoors or exposed to UV light will produce vitamin D.
  • Egg yolks are also a good source, with a single egg containing 37 IUs of vitamin D.
  • Cow’s milk is also a good source of vitamin D, with about 80-110 IUs in each cup. Note, most cheeses contains little to no vitamin D. Fortified nondairy milks and soy milk contain similar amounts.

Pregnancy Minute: Each segment, I’ll do a quick pregnancy minute for anyone wanting to become pregnant, already pregnant, or post-partum. Vitamin D is incredibly important during this period of your life! Vitamin D aids in implantation, supports fetal growth and skeletal development (including teeth), regulates placental function and placental hormone levels, regulates blood sugar and insulin levels, promotes maturation of fetal lungs, and helps regulate blood pressure. Studies show mamas that maintain adequate vitamin D levels have a lower risk of gestational diabetes, preeclampsia, and preterm birth. For breastfeeding mamas, continuing to maintain adequate vitamin D is beneficial for both you and baby, and in fact vitamin D needs are even higher than in pregnancy!

For more information about anything discussed, reach out to me at or call our office line at 337-948-0561 and ask to speak to the nutrition agent, Breanna Staab. You can also visit our parish Facebook page, St. Landry Parish Extension Office – LSU AgCenter for posted recipes. All of June, the posted recipes will include foods high in vitamin D!

Manson JE, Cook NR, Lee IM, Christen W, Bassuk SS, Mora S, Gibson H, Gordon D, Copeland T, D’Agostino D, Friedenberg G. Vitamin D supplements and prevention of cancer and cardiovascular disease. New England Journal of Medicine. 2019 Jan 3;380(1):33-44.

Mulligan, Megan L., et al. “Implications of vitamin D deficiency in pregnancy and lactation.” American journal of obstetrics and gynecology 202.5 (2010): 429-e1