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The REAL Deal on Vitamin D


Vitamin D is actually a hormone - not a vitamin.

Vitamin D is a hormone the kidneys produce that controls blood calcium concentration and impacts the immune system. The presence of Vitamin D is needed to promote balance of thyroid hormones and prevent autoimmune thyroid disorders such as Hashimoto’s thyroiditis. Low levels of Vitamin D are associated with decreased production of sex hormones, which includes testosterone, progesterone and estrogen. Vitamin D is also useful in maintaining Estrogen balance. In patients with elevated estrogen  compared to progesterone; optimal levels of Vitamin D have been shown to have lower estrogen levels which can limit common symptoms such as weight gain, insulin resistance, PCOS and irregular menstrual cycles.

 Though not a hormone; Serotonin and Dopamine are also greatly affected by Vitamin D status. This is likely why depression is linked to winter months where most are exposed to less sunlight which is used to assimilate Vitamin D in the body.

The REAL Deal on Vitamin D

Vitamin D is a fat-soluble secosteroid prohormone most known for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects.

In humans, the most important compounds in this group are vitamin D₃ (cholecalciferol) and vitamin D₂ (ergocalciferol). We only get about 10% of Vitamin D our body needs through food.  It is not naturally occurring in many foods, but you can get it from fatty fish (such as salmon, mackerel, and sardines), pasture-raised eggs (specifically the egg yolk), grass-fed dairy (butter, cheese, and yogurt), grass-fed beef, mushrooms and cleanly sourced animal liver. A breakfast of 2 eggs with mushrooms sauteed in grass-fed butter and served with grass-fed beef sausage would be the perfect Vitamin D-packed breakfast!


Your body makes the other 90% of the vitamin D in your body endogenously when UV (more precisely, UVB) rays react with a compound (7-dehydrocholesterol) in the skin.  Notice the word cholesterol in the last sentence?  More on that another time! I believe it is also important to note here that sunscreen, while essential to prevent skin cancer, can also prevent the body from making the necessary amounts of Vitamin D by blocking the absorption of UVB rays.

Vitamin D plays an essential role in the human body but more recently it is known for its role in the immune system. Unlike other vitamins, we get only about 10% of the Vitamin D we need from diet and the other 90% needs to be made by the body. Between genetic DNA alterations, lack of sun exposure, obesity, and inflammation it is no wonder over 40% of the American population is severely deficient in this nutrient.

Cancer Prevention​

Populations living in Southern areas tend to exhibit lower cancer rates in particular cancers compared to those living in the northern hemisphere. This correlation of sunlight and cancer has led researchers to make the connection between vitamin D status and cancer risk.  Supplementation of Vitamin D has shown to reduce the risk of various cancers such as colorectal, breast, prostate and ovarian cancer.


For many, it is not ideal or possible to get adequate vitamin D from the sun, which is why supplementing with Vitamin D is essential. Depending on the severity of Vitamin D deficiency; supplementation of 2,000 IU to 5,000 IU daily is recommended for repletion. It is important to consider the form of Vitamin D as well as other nutrients that enhance the absorption of vitamin D and enhance the many benefits of Vitamin D.  As vitamin D is essential in promoting calcium absorption; Vitamins K1 and K2 should be added to your supplemental Vitamin D.  Vitamin A is also important to consider while supplementing with Vitamin D as it can protect from Vitamin D toxicity.

Bone Health

Inadequate levels of Vitamin D are frequently associated with osteoporosis, osteopenia and increased risk of bone fractures, however, Vitamin D is also useful in increasing muscle strength. Unfortunately, muscle mass begins to break down as we age so maintaining adequate levels is vital.

Recommended Daily Allowance (RDA)

The Recommended Dietary Allowance (RDA) for Vitamin D is 400IU daily for ages 0-12 months, 600IU per day for ages 1-70, 800OIU daily for adults aged 70+.

Most laboratory tests and physicians recommend a blood level of 20-30 ng/ml to avoid being Vitamin D deficient. This set range is based on the average American and does not consider levels needed for optimal health but instead is a range to prevent deficiency. One would need far more than 20-30 ng/ml (likely 60-75ng/ml ) for optimal health and to prevent chronic illness. Vitamin D has an influence on nearly 3,000 genes, making it a big player when we talk about the body’s immune system.

Honey Ginger Baked Salmon


1.5 pounds center-cut salmon

2 tbsp honey

2 tbsp soy sauce (use coconut aminos if soy free)

2 cloves minced garlic

1 tsp minced ginger

1 tbsp rice vinegar

1 tsp toasted sesame seeds

1 tsp toasted sesame oil

4 scallions thinly sliced, white parts only

½ tsp kosher salt

¼ tsp white pepper


  1. Preheat the oven to 400 degrees F and place the salmon in an oven-safe baking dish.

  2. In a small bowl, whisk together the honey, soy sauce, garlic, ginger, rice vinegar, sesame seeds, and sesame oil until well combined.

  3. Pour the sauce over the salmon. Sprinkle the top with scallions, salt, and pepper.

  4. Transfer to the oven and bake the salmon for 18-20 minutes, basting halfway through.  Salmon is finished when it easily flakes with a fork.

  5. Remove the salmon from the oven and let cool for 5 minutes. Meanwhile, spoon the sauce again over the top of the salmon and garnish with additional toasted sesame seeds and scallions, if desired.

The McCahill Group 

5510 Cascade Rd SE Suite 230, Grand Rapids, MI 49546

Tel: (616) 493-0476

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