25 Jun

The Tremendous Trio: Magnesium, Vitamin D, and Calcium

Magnesium, Vitamin D, and Calcium. If you are like a lot of us, you are not actively looking at nutrition labels to ensure these minerals and vitamins are adequately present in your daily diet. As with all nutrients, taking them through food is ALWAYS the best option, as nutrients are co-dependent. They must be eaten in certain combinations for them to have full effect. This does NOT include multi-vitamins, where a large percentage of those minerals have to compete with each other (and very little are actually absorbed anyways). Deficiencies in these or any other nutrient can lead to elevated or sustained levels of pain and inflammation.

Physical therapist and instructor for the Institute of Physical Art, Cheryl Wardlaw, detailed some amazing research on the power of magnesium, vitamin D, and calcium in her book “Taming Pain”. We highly recommend ordering and reading Taming Pain in its entirety for yourself. This article further details one aspect of the numerous topics outlined in the post: Health and Wellness: What Every Patient Should Know.


Magnesium is involved in over 300 chemical reactions in the body including protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation! It is needed to utilize Vitamin D for bone health and regulate calcium for total body homeostasis. It’s one of those minerals that most of us are deficient in. Some fun facts about why we might be deficient:

  • Approximately 60% of the magnesium that we eat is NOT absorbed. 
  • Magnesium levels in food are 50% lower than they were 100 years ago.
  • Cooking removes about 25% of the magnesium found in foods. 
  • Less than 50% of the magnesium in supplements are absorbed.
  • If calcium is taken with magnesium, the body will preferentially absorb calcium before magnesium.
  • Phosphates in soft drinks and lunch meats bind with magnesium, causing it to pass from your body without being absorbed!

Magnesium’s recommended daily value is 420 mg. 

Dietary surveys have shown that at least 50% of the United States is magnesium deficient. This has big implications on how much vitamin D and calcium are able to be absorbed. 

How do you know if you are lacking magnesium? Often the symptoms alone can be an indicator that your body is magnesium deficient. Some of these symptoms are muscle cramps, migraines, joint pain, hyperactivity of nerves, poor sleep, and attention deficits. Bloodwork is a great way to check for levels of minerals in your body. However, even if the blood work comes back normal you may still have moderately to severely depleted cellular levels of magnesium. The risk of overdosing on magnesium is highly unlikely IF it comes from food. Taking too much magnesium supplementation may give you diarrhea, so eating your magnesium from a food source is best. 

Some food options for ensuring you are taking the recommended amount of magnesium include:

  • Almonds ( 1 ounce or about 23 almonds = 20% DV)
  • Cashews ( 1 ounce or about 18 cashews = 18% DV)
  • Shredded wheat cereal ( 1 serving = 15% DV)
  • Black beans – cooked ( ½ cup = 14% DV)

One of the easiest (and most fun) ways of ensuring you are getting the recommended amount of magnesium is through epsom salt baths! You can soak the feet or the whole body. Magnesium through an epsom salt bath does not have to compete with calcium in the GI tract, does not get removed by the kidneys, and doesn’t cause diarrhea!  

Vitamin D

Vitamin D is needed for the body to absorb calcium. It is also critical for bone growth and bone remodeling. Along with calcium, Vitamin D helps to lower the risk of developing osteoporosis. Vitamin D also plays a role in lowering inflammation levels. 

Wait, I thought Vitamin D came from the sun? Why should I worry about eating it? The sun plays a crucial role in Vitamin D production in the body by interacting with cholesterol in the skin. The UVB light rays interact with cholesterol to create Vitamin D3, the precursor to Vitamin D that our body uses. So getting more sunlight will help me lower my cholesterol levels? Unfortunately not, according to recent research. UVB rays also don’t penetrate glass. Season, time of day, skin melanin, age, smog and sunscreen can all negatively affect how much Vitamin D can be created through skin absorption. This whole process of converting sunlight to Vitamin D requires Magnesium to complete the process. If there is a deficiency in magnesium, there is a much higher chance you will have a Vitamin D deficiency as well. 

Vitamin D’s recommended daily value is 1,500 IU. Remember that a deficiency of Magnesium will lead to a deficiency of Vitamin D as well. 

Additional sources of Vitamin D include:

  • Cod liver oil (1 tablespoon = 1,360 IU)
  • Salmon (cooked, 3 ounces = 570 IU)
  • Mushrooms (white, raw, sliced, exposed to UV light, ½ cup = 366 IU)
  • Fortified milk (1 cup = 120 IU)
  • Fortified cereal (depends on Vitamin D fortification)


Calcium is well known for its role in bone health. Eating the recommended daily amount of Calcium lowers risk of bone loss by 30-50%! Additionally, calcium is important for the health and function of blood vessels and nerve function. 

If you get too many phosphates from cola or preserved meats your body will burn through magnesium and vitamin D stores. This prevents optimal absorption of calcium which can lead to deficiencies. 

The recommended daily amount of calcium is between 1000 mg and 1500 mg. However, we can only absorb about 500 mg of calcium at a time, so spacing out the intake is important. Also, keep in mind that calcium and magnesium compete in the gut for absorption priority, and calcium always wins a head to head battle.

Calcium can come from numerous sources. Fortified food options like some cereals can have 1,000 mg or more of Calcium!

Some food options for calcium include:

  • Yogurt (8 ounces = 415 mg)
  • Almonds (1 cup = 369 mg)
  • Milk (1 cup = 299 mg)
  • Mozzarella cheese (1.5 ounce = 333 mg)
  • Broccoli (raw, ½ cup = 21 mg)

Calcium levels can elevate to dangerous amounts If Vitamin D is not able to convert (using magnesium) into its active form. This can trigger your body’s hormones to draw calcium from your bones, and deposit it into your arteries and soft tissue. No good! 

There is no better time to start changing the way you look at your diet than now! 


Let’s recap the interaction between Magnesium, Vitamin D and Calcium. Vitamin D is needed for your body to absorb calcium. Magnesium is needed for your body to create Vitamin D. Calcium is needed to regulate and balance Magnesium levels and vice versa. 

As you can see, Magnesium, Calcium and Vitamin D all play important roles in regulating the health of our body. Each mineral and vitamin is dependent on the next for efficient function. Ingesting your essential nutrients through food is ALWAYS the best choice, and supplementing from pills or other external sources should be considered a last option. 

Sample Meal Plan

Here is an example of a meal plan that can help you achieve your recommended intake of nutrients:

  • Breakfast – 3 cups of yogurt ( 100% calcium)
  • ¼ cup seeds ( 100% Vit E)
  • Lunch – 7 oz fish (100% Omega 3) (100% Selenium)
  • 1 baked potato ( 50% potassium) (25% Vit B6)
  • 1 ½ cup spinach salad ( 50% Magnesium, 50% Vit A, 50% copper, 25% Vit B6) with ½ cup red bell pepper ( 100% Vit C)
  • Dinner – 10 oz shrimp (100% Vit D); 
  • 14 oz lean beef (100% zinc) 
  • 1 ½ cup spinach salad ( 50% Magnesium, 50% Vit A, 50% copper, 25% Vit B6); 
  • 1 baked potato ( 50% potassium) (25% Vit B6)
  • Night time snack – 2 tablespoon Cherry Juice Concentrate (The BEST anti-oxidant!)

Diets are a very personal choice, and there are many options when it comes to how and where we load up on fuel. If you have additional questions on how to ensure you are getting adequate amounts of Magnesium, Calcium and Vitamin D, consult with your doctor, and reach out to a registered dietitian!

About the Author

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Ian McVay

Ian served in the US Navy submarine force as a torpedoman for 5 years where he developed the drive for excellence which is seen in each treatment and patient interaction. Ian is a Certified Laser Therapist, a Certified Kinesio Taping Practitioner and a Credentialed Clinical Instructor. While working hand in hand with therapists and spinal surgeons in San Diego, Ian worked with his patients to exhaust all avenues of conservative care prior to surgical or other invasive options such as injections. In addition, he has developed expertise in working with a large variety of patients including: orthopedics, dementia, long-term care, post-surgical and neurological pathologies. Ian heads up the laser therapy division of the IPA Physio Portland office as well as working with patients in critical exercise and movement strategies.