Can you feel it? This August is a hot month—literally and figuratively.
It’s an election year; events are erupting all around the world; and, stateside, the fear-mongering is ramping up… Bird flu! Monkey pox! Another potential pandemic!
If there is anything the last 4 years should have taught us, it is this…DO NOT FALL FOR THE FEAR-MONGERING!
Being in a constant state of fear and anxiety only weakens your immune system, leaving you vulnerable to opportunistic viruses and pathogens.
While we cannot control what happens outside of us, we can be proactive in creating a healthier reality for ourselves; for example, having a stronger immune system this fall.
In the same way that squirrels start gathering nuts in the fall in anticipation of winter, August is the perfect time for humans to shore up their immune-supporting nutrient reserves before cooler weather arrives. I’m talking specifically about sunlight exposure, Vitamin D3 and magnesium, the anti-stress mineral.
I’m just back from Maine where I did exactly just this. Spending my days at the beach and in the ocean was a relaxing and pleasurable way to absorb sunlight that enables the body to make Vitamin D. And the ocean is a potent source of magnesium, which has a calming effect on the body and, is, perhaps, one reason why so many people feel an affinity for the ocean.
A beach vacation isn’t necessary, however. You can increase your intake of these immune-boosting nutrients wherever you live. Simply be mindful of taking time for outdoor sunlight exposure. And you can increase your Vitamin D and magnesium intake through food choices, supplementation and/or transdermal means.
How these nutrients help boost your immune system
1. Sunlight: This is an essential nutrient for human health…and for our immune function.
Scientists have long recognized the value of exposure to UVR (ultraviolet radiation) in sunlight. From the late 19th century to the mid-20th century, heliotherapy, a.k.a. “sunlight therapy”, was used to treat infectious diseases, like tuberculosis, and various health conditions, including gout, rheumatoid arthritis, asthma, rickets, etc. (1). Studies showed that exposing patients to controlled amounts of sunlight dramatically lowered elevated blood pressure; lowered cholesterol in the blood stream; lowered blood sugar in diabetics; and increased the number of white blood cells, a part of your immune system that helps protect your body from infection (2, 3).
Optimal sun exposure is associated with improved immune function, and, consequently, a lowered risk of heart disease, some cancers, including breast, prostate, pancreatic and (ironically!) melanoma, osteoporosis, multiple sclerosis (MS) and Type 1 diabetes (4). Getting a healthy dose of sunshine can also boost mood, enable better DNA repair and reduce lesions in psoriasis, eczema and vitiligo (5).
Sunlight (natural light) is key in helping regulate our circadian rhythms, which are crucial for rest and repair, as well as activating our immune system.
Circadian rhythm refers to the 24-hour internal clock, or “master clock” in our brain, that regulates cycles of alertness and sleepiness via light changes in our environment (6). Many of our bodily functions and processes are affected by circadian rhythms; in particular, our sleep-wake cycles, as well as body temperature, hunger and eating patterns, and activity levels.
According to the National Institute of Mental Health:
“Solar radiation activates biochemical events in our bodies that are involved with the regulation of stress and fatigue, endocrine (hormone) control, timing of our biological clocks, immunological responsiveness control of viral and cold infections and the dampening of functional disorders of the nervous system.” (7).
Sleep disorders, like insomnia, are linked to artificial light exposure—from television, computer and phone screens—after sundown, which suppresses melatonin production and can disrupt our sleep cycle.
One of the biggest benefits of sun exposure is that it enables your body to make Vitamin D, also known as “the sunshine vitamin”.
How to practice “safe sun” exposure
During the summer, exposing large areas of bare skin (without sunscreen)—like your back—to sunlight, specifically, ultraviolet B (UVB) rays at midday, is one of the most natural—and efficient—ways that your body can make vitamin D (8). Aim for 10 to 20 minutes around midday (12noon to 1pm), depending on your sensitivity to the sun and skin type, from fair to dark (9). Afterwards, you can apply sunscreen to face and body as needed.
Vitamin D3 is made from cholesterol in the skin. The sun’s energy turns a chemical in your skin into pre-vitamin D3, which is carried to your liver, then to your kidneys to transform it to the active form of Vitamin D that your body can use (10, 11).
That said…do NOT automatically assume that being “tan” or “getting color” after sun exposure means that you have achieved optimal levels of Vitamin D3.
Various factors and health conditions can prevent the body from efficiently converting sun exposure to vitamin D, including (12, 13):
- Age: Older people (aged 50 or older) have thinner skin which can limit the amount of Vitamin D being produced.
- Skin color: Darker skin requires much more time in the sun to make vitamin D than fair skin.
- Amount of skin exposed: More skin exposure = greater vitamin D production. Less skin exposure = less vitamin D produced
- Sunscreen: Wearing sunscreen can slow down or prevent your body from producing vitamin D.
- Digestive health problems / Gut health issues: g., Crohn’s, ulcerative colitis, IBD, non-celiac gluten sensitivity, etc.
- Absence of gallbladder (as in…it has been removed).
- Kidney disease.
- Liver disease.
- Autoimmune disorders: g., rheumatoid arthritis, lupus, Hashimoto’s thyroiditis, etc.
- Obesity: Being obese is associated with reduced Vitamin D production in the skin and overall vitamin D deficiency.
- Having had a gastric bypass.
2. Vitamin D: An optimal level can help reduce your risk of getting respiratory tract infections, like colds and influenza-like illnesses, including COVID-19 (14).
The two main forms of Vitamin D are Vitamin D3 and Vitamin D2. Found in animal foods, Vitamin D3 is also produced by your skin from sun exposure, whereas Vitamin D2 is nominally present in fungi (e.g., mushrooms) and yeast and is often used to fortify foods, like milk. Going forward, please note that when I say “Vitamin D”, I am referring specifically to vitamin D3, which studies indicate is more effective than vitamin D2 in raising blood levels of Vitamin D (15, 16).
A fat-soluble vitamin, Vitamin D is also a pro-hormone, produced in the kidneys, that promotes calcium absorption, contributing to healthy bones. Because virtually every cell in the body has a Vitamin D receptor—from your skin, breast, colon and pancreas, to your brain, teeth, spinal cord and more—many bodily processes are affected by Vitamin D (17).
Vitamin D also regulates the immune system, cell growth and muscle function. Low levels of vitamin D are also associated with increased autoimmunity, as well as increased susceptibility to infection (18).
*Autoimmunity is when the body’s immune system mistakes its own healthy cells and tissues as “foreign” and attacks them. Examples of autoimmune diseases include MS, lupus, Type 1 diabetes, Hashimoto’s thyroiditis, rheumatoid arthritis and more (19).
Many studies show that vitamin D3 supplementation can help reduce risk of colds and flu, a.k.a. URIs or upper respiratory infections (20).
In a 2013 meta-analysis of 11 randomized controlled trials, researchers found that Vitamin D has a protective effect against respiratory tract infections with once / daily Vitamin D supplementation being most effective (21).
In another 2017 study published in the British Medical Journal, researchers found that Vitamin D supplementation helped protect against acute respiratory infection. The benefit was greater in study participants who regularly supplemented—daily or weekly—with Vitamin D. The protective effects of supplementation were strongest among those participants who had severe vitamin D deficiency at the start of the study (22).
More recently, in a 2022 study published in Nutrients, researchers found that daily Vitamin D3 supplementation was associated with a lower risk of influenza-like illness (ILI), including COVID-19, among healthcare workers who supplemented with 5,000 IU of Vitamin D daily for 9 months (23).
Test: Don’t Guess
Vitamin D deficiency affects an estimated 50% of the population worldwide (24). In the U.S., approximately 40% of Americans are notably deficient in Vitamin D; this means having a serum blood level of Vitamin D below 20 ng/mL (50 nmol/L), according to a 2018 study, published in Cureus (25).
A blood test is the only way to know if you are getting enough Vitamin D—or not. An optimal Vitamin D range is between 50-70 ng/mL. If your Vitamin D is low, you can be proactive about increasing sun exposure and/or supplementing with Vitamin D.
You can ask your doctor to order a Vitamin D test, specifically, the 25(OH)D test.However, be forewarned: many insurance companies no longer cover a Vitamin D test.I learned this from personal experience. Back in 2020, my functional medicine doctor wrote a lab script that included Vitamin D. When the phlebotomist reviewed my script, she told me that my insurance would not cover the Vitamin D test; if I wanted it, I would have to pay $300 (for that one test) out-of-pocket! I declined. Since then, I have ordered my own Vitamin D3 test (listed under the “Nutrient Panel”) via this direct access lab service. No doctor’s visit required.
Sources of Vitamin D
Unfortunately, few foods naturally contain Vitamin D—and only small amounts at that. These include fatty fish, like salmon and sardines, beef liver, egg yolks and mushrooms. So, it is impossible to get the Vitamin D your body needs through food alone. The best ways to optimize your Vitamin D level is by:
1) Sunlight. Exposing bare skin (no sunscreen) to sunlight, specifically UVB rays, around midday during the summer, can be an efficient way to make Vitamin D. That said…how much vitamin D you can make also depends on where you live, season, time of day, latitude, skin color and amount of skin you expose.
2) Supplementation. There are many types of Vitamin D supplements from which to choose. I strongly recommend (and I also take it) this easy-to-take brand of vitamin D3 in liquid form, which includes vitamin K2, an essential co-factor. You can also take 1 teaspoon of cod liver oil daily to boost vitamin D levels.
3. Magnesium: This anti-stress mineral plays an important role in supporting immune function.
Magnesium is a vital, multi-tasking mineral.
In the human body, magnesium powers 80% of metabolic functions—chemical reactions that occur in our cells to keep us alive, making it a foundational mineral for overall health. Magnesium is essential for producing energy, blood sugar balance, muscle growth and repair, bone development, regulating hormone function, cardiac conduction, nerve function, balanced mood and much more. If you are low in magnesium, virtually every system in your body suffers—including your immune system (26, 27).
Magnesium and Your Immune System
According to a 2023 review published in Journal of Health, Population and Nutrition:
Magnesium is essential for optimal immune function and regulating inflammation (28).
A magnesium deficiency can lead to temporary or long-term immune dysfunction. Magnesium plays a significant role in the immune response against cancer cells and infectious pathogens. Magnesium also regulates inflammation (for example, a low level of magnesium is indicative of inflammation in the body) and apoptosis, or programmed cell death (29).
T cells are a type of white blood cell that enables your immune system to fight off invaders, like viruses. Researchers report that having a sufficient level of magnesium increased the effectiveness of T cell performance. On the other hand, low magnesium levels were associated with more rapid disease progression (30).
While Vitamin D plays a key role in regulating the immune system, magnesium is necessary for the activation of Vitamin D (31, 32).
In a 2020 study conducted by Grassroots Health (a vitamin D research organization), researchers used the nutrient intake data and blood level tests from over 3,000 participants to assess whether supplementing with magnesium affected Vitamin D levels. What they found:
Participants who took a higher dose of supplemental magnesium also had higher vitamin D levels no matter what their Vitamin D intake. Participants who only took Vitamin D—without magnesium—had to take 146% more supplemental vitamin D in order to achieve a “sufficiency” range (33).
Unfortunately, like Vitamin D, the vast majority of Americans are magnesium deficient. According to magnesium expert Dr. Carolyn Dean, a conventionally trained medical doctor and naturopath: the rate of magnesium deficiency is likely prevalent in at least 80 percent of the US adult population (34).
Why? Magnesium deficiency can be attributed to the following (35, 36):
- Eating a Standard American Diet, which includes ultra-processed and convenience-based foods that are high in sugar, flour, refined carbohydrates and unhealthy fats by way of toxic seed oils.
- Taking medications that deplete magnesium as a side effect. g., antibiotics, birth control/HRT, acid blockers, like Nexium or Zantac; immunosuppressants; blood pressure meds; diuretics and many more.
- Lifestyle. Alcohol consumption. Caffeine intake. Drinking fluoridated water. Consumption of refined grains, junk food and /or conventionally grown (with pesticides and herbicides) produce and/or meats. Antacids. Exercise/athletic performance (requires more magnesium). Stress or trauma of any kind.
- Modern farming practices—even if organic—have stripped our soils of essential minerals, including magnesium. It is estimated that the mineral content of vegetables has dropped dramatically—by 80 to 90%—over the last 100 years. *This makes it difficult to achieve optimal magnesium levels through food alone—no matter how well you eat.
Should You Test?
Because the modern world in which we live is highly toxic and stressful, we can virtually assume that everyone is magnesium deficient to a greater or lesser extent. However, I am a big believer in testing first before randomly supplementing. It’s like trying to lose weight without ever stepping on a scale first. Knowing the extent to which you may or may not be deficient in a nutrient can enable you to supplement accordingly.
*Note: Up to 99% of magnesium is present in your cells. Only a tiny amount—apx. 1%—of magnesium is actually present in your bloodstream. This means a standard serum magnesium test is not a reliable indicator of your magnesium status (37, 38).
This is why you should always request a Magnesium RBC (red blood cell) test for an accurate assessment of your magnesium status. Again, I typically order my own Magnesium RBC test (listed under the “Nutrient Panel”) via this direct access lab service.
Sources of Magnesium
Food sources of magnesium: Seaweed (kelp, dulse); nuts (almonds, cashews, walnuts); pumpkin seeds; leafy greens (kale, collards, mustard greens, spinach, Swiss chard); some fatty fish (salmon, mackerel and halibut); pseudocereals, like buckwheat and quinoa; and dark chocolate.
Unfortunately, most people do not reach the Daily Value (DV) of 420 mg for magnesium (39). An average good diet that included magnesium-rich foods would supply roughly 250 mg of magnesium…however, your body can only actually absorb about half of the magnesium (apx. 125 mg) you consume, according to Dean. Researchers feel most people would benefit from magnesium supplementation (40).
Supplementation: There are different types of magnesium. Some like magnesium oxide can have a laxative effective (a benefit if you have constipation) but is poorly absorbed by the body. These are forms of magnesium that I favor and are generally well absorbed at a cellular level. *NOTE: If you have—or are being treated for kidney disease—please consult your healthcare practitioner first before supplementing with ANY FORM of magnesium.
If a beach getaway is not in the cards, try a transdermal means of bringing the relaxation benefits of the ocean to you: take a hot soak in magnesium chloride or magnesium sulfate, both forms of magnesium found in the ocean.
1) Magnesium Chloride. This is found in deep sea water. Add 2 cups to a hot bath or 1 cup to a foot soak.
2) Magnesium sulfate (Epsom salts). Another naturally occurring form of magnesium that the ocean contains. Also known as Epsom salts. Add 2 cups to a hot bath or 1 cup to a foot soak.
Other options include:
3) Magnesium malate. I, personally, use the malate form of magnesium as it has an 85% absorption rate. This formulation also includes vitamins B6 and B12, which helps increase the amount of magnesium that can enter your cells. It is a great option for replenishing magnesium levels.
4) Magnesium glycinate. Generally well absorbed by your cells. Magnesium glycinate is a form of magnesium that is least likely to have a laxative effect. A 2013 study found that 400 mg of magnesium glycinate supplementation over a 6-week period raised magnesium levels for people who had had bariatric surgery. Supplementing with 400 mg of magnesium glycinate over 4 weeks also helped improve exercise performance in physically fit young adults (41).
Sources
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