This section doesn’t currently include any content. Add content to this section using the sidebar.

Image caption appears here

Add your deal, information or promotional text

Vitamin D: Photosynthesis, Longevity, Cofactors and Genes

by Travis Gerhart
Vitamin D: Photosynthesis, Longevity, Cofactors and Genes

Hey, sun-soakers! Ever noticed how lounging under the sun's rays feels like a warm hug from the universe? It's also your body's secret weapon for producing its own stash of vitamin D — famously known as the 'sunshine vitamin'! But, plot twist, an astonishing 1 billion people worldwide have vitamin D deficiency. Additionally, around 50% of the global population has vitamin D insufficiency. [1, 2]

Don't play hide-and-seek with your vitamin D. We all need it! This mighty vitamin is the mastermind behind your rock-solid bones, your muscles' smooth moves, and your immune system's superpowers. So, fasten your seat belts as we dive into the world of vitamin D benefits and uncover the formula to grab your daily dose of this sun-kissed vitamin!

Isn't it true that I can get all the vitamin D I need from just being outside in the sun a little bit every day?

Photosynthesis of vitamin D isn't as easy as it seems.

I was introduced to this vitamin D and insufficiency concept "way back" in 2002 (yikes). Thank you, Dr. Mercola. If someone had asked me what I thought my vitamin D level was, I would have sworn I was good to go. I mean, I was outside doing something almost every day. As it turns out, my test results fell in the insufficient range and much farther from ideal than I would like to admit.

I grew up in Iowa, helping on the family farm after school, on weekends, and in the summer, boating on those good-weather Sundays. Honestly, half the year, we were probably good. Fall, winter, and early Spring were another story. More on this later.

The schedule I just described was before I had a job and worked indoors for 90% of vitamin D producing daylight hours, as many adults do.

The sun is still out. I can still get vitamin D, right?

Well, as it turns out, I was incorrect in that thought. I had no idea about the angle of the sun's rays entering the atmosphere and why that may or may not be significant. In reality, photosynthesis of vitamin D isn't as easy as it seems due to lifestyle factors like working (boring) and the nuances of our genetics.

Where you live, your approach to sunscreen, your genetics, and your indoor vs. outdoor work status all affect your body's ability to produce and maintain vitamin D. The reality is that when accounting for these factors, it may be impossible to get your vitamin D blood level high enough to enter the health-promoting or ideal stage, let alone maintain that level consistently throughout the year.

Let's talk about that whole "angle of the sun" thing and why your location matters to how much vitamin D you can create from the sun's rays.

Sunshine Calendar produced by GrassrootsHealth

This Sunshine Calendar gives representation to your ability to create vitamin D by month.
Image Credit: GrassrootsHealth

The body synthesizes vitamin D from the sun's UVB rays which only enter the atmosphere when the sun reaches 35 degrees to the horizon. During the summer, your vitamin D window may be only from 11a-4p, depending on where you live.

UVA rays, which are the rays that damage skin, continue to enter the atmosphere throughout all hours of the day. Sunlight exposure outside the UVB window does not contribute to vitamin D generation; only the skin-damaging rays are present. The potential for UVA to damage skin is much lower in the morning and evening, as represented by the low UV Index at those times. The goal would be to get responsible sunlight exposure during the vitamin D (UVB) window.

Other factors prevent vitamin D absorption during this window:
• Sunscreen blocks UVB rays from stimulating the skin to produce vitamin D, even if you are in the sun during solar noon. Shoot for sensible sun exposure before applying sunscreen for maximum benefit.

• Covering up thoroughly with clothing and large-brim hats creates a physical barrier from the sun and prevents UVB rays from stimulating photosynthesis. Covering sensitive skin can be protective, while scheduling sensible sun exposure before covering up can offset this effect. The larger the skin area exposed, the more efficiently vitamin D is produced, and the less likely burning occurs. Exposing more skin for less time ensures you do not overexpose yourself and burn.

• Your skin's pigment will affect how quickly you produce vitamin D in the sun. Pigment means melanin, and the darker means, the more of it. Melanin acts as a natural sunscreen. This is why you seem less sensitive to sunburns when a lovely tan sets in. Darker skin contains more melanin, which acts as a natural sunscreen. Skin pigment intensity is graded on the Fitzpatrick scale, which classifies skin types based on response to UV exposure. To explain the Fitzpatrick scale further, someone with skin type VI could require 60 minutes of sun to make the same amount of vitamin D as a skin type II person could produce in 6 minutes. That's a pretty significant difference, don't you think? Follow the button at the bottom of this section to find your skin and UV sensitivity score.

• As we age, we make less of the vitamin D precursor in our skin. So much so that by age 70, our capacity to produce vitamin D reduces by 25-30%. Less precursor is one of the main reasons for this age group's vitamin D deficiency or insufficiency.

If you live North of the 35th Parallel, you live in a vitamin D 'dead zone' from October to April. Landmarks of the 35th Parallel include the Northern border of Georgia, Oklahoma City, Albuquerque, and the California/Nevada/Arizona tri-point. The Northern two-thirds of the US experience peaks of the vitamin D window from June through August, while tapering occurs during May and September.

My favorite way to track my vitamin D level is with the D-Minder App. It uses your location data to reveal your available vitamin D window daily and in real time. The app will also allow you to track supplement doses daily or weekly and enter your blood test results when you get them.

From there, it will estimate your vitamin D levels throughout the year. The best part of this app is a sun exposure timer to prevent burning based on your skin type score. It's a very handy tool!

Vitamin D is one of the most critical and influential vitamins for health and longevity.

I've been inspired by this topic for almost 21 years now. Vitamin D was one of the first nutrients I obsessed over during Biochemistry in college, and it started a whole thing for me on how to apply biochem to everyday life.

Ok, getting back on track now.

How does vitamin D relate to health and longevity, and what does it do that other vitamins don't?

Vitamin D wears two hats—one as a nutrient and another as a hormone. Almost every cell benefits from vitamin D's cascading effects to support hundreds of daily metabolic reactions. This is due to a vitamin D receptor (VDR) found in most human tissues and having more than 1000 target genes. [3]

Getting enough vitamin D can help support the health of many organs and systems, such as the brain, heart, lungs, muscle, bone, immune, and reproductive. However, major or minor, vitamin D deficiency can lead to multi-system deficits that wreak havoc on health.

How can I get more vitamin D?

The sunshine vitamin offers enhanced health benefits during sun exposure. Sunshine also helps the body produce serotonin, endorphins, and melatonin. These molecules specialize in mood-boosting, pain relief, relaxation, and immune system support. Vitamin D is also available in certain foods and supplements.


Get all the latest news and updates by subscribing to The Supervital Journal by Best Health Co! Join today and receive 25% OFF your first order 🍄

How much vitamin D should I get?

According to GrassrootsHealth, the optimal range seems to be 40 to 60 ng/ml. GrassrootsHealth is a nonprofit public health research organization dedicated to connecting the dots from vitamin D research to education and public action. Check them out by clicking on one of the chart images used in this article. GrassrootsHealth produces a lot of great information.

The only way to know if you are getting enough vitamin D is to get a blood test. The best frequency for testing seems to be every six months and can be as easy and convenient as a mail-in finger-prick test in your home. This way, you can see two perspectives: how the combination of supplementation and sun exposure affected your results during the summer and how your supplementation and food affected your results during the winter.

A couple of testing cycles will give you an excellent idea of how your lifestyle supports your vitamin D blood levels and where you likely need to make changes.

I prefer the at-home style of finger-prick vitamin D tests. They are easy and relatively cheap. Here are a few that I have used from reputable companies. Their web interface also allows for tracking your results over time.

Thorne Vitamin D Home Test

At-home collection kit. Meaningful insights. Personalized plan. This at-home blood test will provide health insights by measuring your level of vitamin D. Results include a personalized health plan. Thorne offers a Subscribe & Save discount of up to 20%. 

Everlywell Vitamin D Home Test

Simple testing done conveniently at home. Easy to understand results to help you gain meaningful insights into your vitamin D levels. The testing is performed by CLIA certified labs and the results are physician reviewed. 

Vitamin D works well with others; it's sympatico.

Vitamin D works alongside many nutrients to affect countless processes within the body. The synergistic effects of these co-nutrients are significant.

Deficiencies can lead to reduced or absent nutritional metabolic reactions. As you can imagine, this can cause problems that usually become evident over many years instead of immediately.

Some of the most common vitamin inadequacies in the US are vitamin D, magnesium, vitamin K, zinc, copper, iodine, omega-3 fatty acids, and calcium.

Interestingly, vitamin D forms a co-nutrient relationship with these nutrients promoting their absorption and assimilation in the body.

Vitamin D increases the absorption of calcium, magnesium, zinc, copper, selenium, and iron from the diet.

It suggests when one is deficient, they all suffer.

Different mechanisms of action on various body systems are at play when discussing these nutrients. Vitamin D's cofactor commonality promotes absorption and how well each nutrient functions.

Vitamin D promotes cognitive function with the help of omega-3 fatty acids.

Calcium and copper, for instance, use vitamin D to support reactions that promote bone health.

Cardiovascular health benefits from vitamin D's relationship with vitamin K1/K2 (MK-4 & MK-7) and omega-3 fatty acids.

The thyroid gland's ability to use iodine improves because of vitamin D, which plays a vital role in metabolism, growth, and development.

The immune system and the transcription factors supported by zinc get a boost from vitamin D.

Finally, magnesium may be the key to maximizing vitamin D benefits throughout the body. Magnesium has a unique role. It's responsible for activating vitamin D and moving it around the body in the blood to reach the target tissues, allowing it to work its magic for our health. [3]

Cooperation is the key, not isolation. Next, let's look at how vitamin D affects our genes and their ability to do what they are supposed to, called gene expression.

Our genes, vitamin D, and the VDR.

Our genes can affect how good we are at utilizing vitamin D.

The active form of vitamin D regulates and expresses over 1000 genes in the body. [4,7]

That's quite a lot and pretty impressive if you ask me!

This involvement is due to the cell's vitamin D receptor (VDR). The VDR allows the formation of a vitamin D response element (VDRE). The VDRE can regulate a gene's function by allowing vitamin D to activate or inactivate a particular gene.

The VDR helps support the function of our DNA, which is critical for healthy aging. Activation of the VDR may be the most crucial function of vitamin D, promoting the balance and stability of healthy cells.

It is estimated that upwards of 35 genes regulate and interact with the concentration of the active form of vitamin D in our body. [8]

Not all of these genes are fully understood. A gene can have different versions, referred to as polymorphism. Genetic variations can offer insight into gene polymorphisms and their functional differences. They are primarily responsible for variance in how our genes are expressed. The differences in our genes will affect our ability to absorb, photosynthesize, and use vitamin D.

Meaning some people have the enhanced ability to make vitamin D from the sun (photosynthesize). The same occurs from the opposite spectrum. Some have a reduced ability to synthesize their own vitamin D.

Similarly, this concept applies to the interaction with vitamin D supplements. Wide-ranging blood concentrations can occur from individuals taking the same amount of vitamin D daily in supplemental form. All depending on a few differences in their genes.

When I hear all this, it generally makes sense. We are all different. Many factors are at play, but it often doesn't enter the thought process when considering taking a vitamin D supplement.

Here are some of my favorite brands that produce high-quality vitamin D supplements.

Thorne Vitamin D 5000 IU

Thorne’s D 5000 is preservative-free, lactose-free, and contains 5,000 IU of high-quality vitamin D3. The D3 form, is more potent and better absorbed form than its D2 form. Thorne offers a Subscribe & Save discount of up to 20%.

Thorne Vitamin D 1000 IU

Thorne’s D 1000 is preservative-free, lactose-free, and contains 1,000 IU of high-quality vitamin D3. The D3 form, is more potent and better absorbed form than its D2 form. Thorne offers a Subscribe & Save discount of up to 20%.

NOW Vitamin D 2000 IU

NOW Supplement's Vitamin D3 softgels supply this key vitamin in a highly absorbable liquid softgel form. As more people avoid sun exposure, vitamin D supplementation becomes even more necessary to ensure that your body receives an adequate supply.

Final thoughts on managing your vitamin D level for the long term. 

Ok, let's put it all together and create an action plan. As with anything, the rest is easy once you figure out the particulars.

First things first when talking about vitamin D management is deciding your vitamin D blood-level goal range.

According to the endocrine society, blood levels of the active version of vitamin D below 20 ng/ml are deficient, less than 30 ng/ml is inadequate, and a range of 30-60 ng/ml is adequate. [5]

Meta-analyses have shown that people with 40-60 ng/ml serum levels have the lowest all-cause mortality. [6]

Based on this information and countless others from GrassrootsHealth, 40-60 ng/ml seems to be the range goal for optimal health.

Chart of how much vitamin D is needed from various sources.

Image created by GrassrootsHealth to visually represent various ranges of vitamin D. 

Now that we have figured out our goal or have some idea, at least. Our genetic variations may make this range challenging to sustain.

So you may be wondering how to manage this?

The first step is to set a concentration goal for the active form of vitamin D in your blood. 40-60 ng/ml seems to be a good start.

Second, combine supplementation and sun exposure and track it via the D-Minder App.

Lastly, test for blood concentrations of active vitamin D to dial in your supplement dose, considering your lifestyle and seasonality as part of the calculation.

The timing of testing seems to work best in the Spring and Fall. Fall to see how you managed your sun exposure in combination with supplementation, and Spring to see how you managed your supplementation without sun exposure through the winter season. Testing will let you know if you need to increase your dose in the winter or keep it at the same level all year. Clarity is the key.

After a few rounds of testing, you will settle into a pattern for appropriate seasonal management of your vitamin D levels for optimal health.


We are huge fans of optimizing our daily interactions across the physical, mental, and emotional spectrum, fostering a lifestyle promoting Supervital Active Longevity.

We can control what we consume and apply to our bodies. We take a holistic approach to nourishment that includes our dietary intake and the mindset we adopt.

Our life strategy is designed as a catalyst, primed to amplify our potential and support aspirations—a foundation to remove distractions and conquer the obstacles in your path.

We invite you to join us on this journey via The Supervital. Join the movement, Besupervital®.

Travis Gerhart, DC, RYT-500

Travis Gerhart, DC, RYT-500

Founder of Best Health Co & The Supervital Journal. Topics focus on the mind, body, & soul aspects of Supervital Active Longevity. Dr. Gerhart enjoys studying the latest developments in biochemistry, phytochemistry, epigenetics, & aging.
@traviswgerhart • @besthealthco

*Statements made on this website have not been evaluated by the U.S. Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Information provided by this website or this company is not a substitute for individual medical advice.



The Remarkable Benefits of Lion's Mane: A Guide to Boosting Brain Health and Mental Acuity

Nov 27, 2023 - by Travis Gerhart

Are you looking for a natural way to boost your brain health and increase the sharpness of your mental motor? Look no further than the remarkable lion's mane mushroom. Known for its unique appearance and delicious taste, this powerful fungus has been used in traditional Eastern medicine for centuries. [1] However, recent scientific studies have highlighted its numerous benefits for brain health and mental gymnastics. From boosting memory and focus to fortifying against age-related cognitive decline, lion's mane mushroom has gained recognition as a potent superfood. [2]In this article, we'll touch on some of the science behind lion's mane mushroom and explore how it can benefit you and your brain. Whether you're a student, a working professional, or simply looking to enhance your overall ninja skills, incorporating lion's mane mushroom into your diet may unlock a sharper, more focused mind and a better version of yourself.

View Details

Adaptogens Unveiled: Nature’s Secret to Bouncing Back from Stress

Nov 17, 2023 - by Travis Gerhart

Holistic health is at the forefront of modern wellness, with individuals seeking natural alternatives for their health and well-being. While this approach may seem like a current trend, the use of holistic practices dates back centuries, with ancient civilizations incorporating elements of mind, body, and spirit into their healing practices.One aspect of holistic health that has gained attention in ancient and modern times is adaptogens. Adaptogens are a class of herbs and mushrooms traditionally used in Ayurvedic and Chinese medicine to promote balance and resilience in the body.With the growing interest in holistic health, there has been a surge in research and interest in adaptogens and their potential role in modern wellness.This article will explore adaptogens' history, traditional use, and the scientific evidence behind their purported benefits to better understand their role in holistic health.

View Details

Unmasking the Sunshield: Why Mineral Sunscreens are the Healthier, Eco-friendly Choice

Jul 07, 2023 - by Travis Gerhart

In our quest for healthy, vibrant skin, sunscreen plays a pivotal role. While we love the sun for the warm, radiant glow it brings, its ultraviolet (UV) rays can be detrimental to our skin's health. Sunscreen helps protect our skin from these harmful rays, reducing the risk of skin cancer and premature aging.Have you ever found yourself wondering what's actually in sunscreen anyway?This brings us to an ongoing debate in skin care and the health community: Mineral-based sunscreens versus chemical sunscreens.Follow along as we take a closer look and explore the health benefits of mineral-based sunscreen and the potential risks associated with its chemical counterparts.Make an informed choice for healthier skin and a healthier planet.

View Details


Get all the latest news and updates by subscribing to The Supervital Journal by Best Health Co! Join today and receive 25% OFF your first order 🍄