How to Choose a Vitamin D Supplement for Brain Health
You may recognize vitamin D as the “sunshine vitamin,” since we produce it by the skin’s exposure to sunlight, but did you also know that the quantities of vitamin D found in most foods is quite low, making it easy to neglect as an essential nutrient? Given this, the combination of less activity outdoors and low consumption readily contribute to vitamin D deficiency. In fact, vitamin D deficiency is extremely common in older adults, affecting up to a staggering 90% of the elderly population.1 This deficiency has been highlighted recently during the Covid-19 pandemic, reflecting its importance in many aspects of health. And one critical area of health that vitamin D plays a vital role in is brain health; vitamin D is brain-relevant in numerous ways, as it is involved in memory and cognition.
Why are we so deficient in vitamin D?
While sunlight is a primary source of vitamin D, certain foods like fatty fish can provide substantial amounts of vitamin D. However, most people do not consume meaningful amounts of such fish in their typical diets. Vitamin D from sunlight is also limited because in geographical regions further from the earth’s equator, the sunlight isn’t intense enough for the body to produce sufficient vitamin D for much of the year. In certain regions, persistent foggy or rainy conditions can also limit sunlight exposure, making it challenging for people to obtain adequate sunlight, especially during winter times of the year. Additionally, the modern world doesn’t allow people to spend enough time outdoors, with a large portion of work and activities being purely indoors, so their exposure to sunlight is further limited. Finally, as we get older, our ability to synthesize vitamin D from sunlight is reduced, so older adults tend to be even more deficient in vitamin D.2
Ways to naturally increase intake of Vitamin D
You can increase your vitamin D levels naturally by consuming more food sources of Vitamin D. These include fatty fish, like salmon or tuna, egg yolks, or foods fortified with vitamin D, such as orange juice or cereal.2 Vitamin D levels can also improve by increasing sunlight exposure. While it’s important to protect your skin from too much sun due to skin cancer risks, research shows that exposure to midday sun can produce meaningful amounts of vitamin D in as little as 10-15 minutes.3 If you want to limit the amount of time you spend in the sun, but maximize vitamin D production, expose more skin to the sun. By increasing the surface area of skin that the sun “touches,” you can increase the amount of vitamin D produced. For example, you may want to protect your eyes and face from potential sun damage and allow most of your vitamin D to be produced from your arms and legs by exposing these areas to the sun. Another factor to consider is that sunscreen is important to protect your skin from the long-term damaging effects of the sun, but it also reduces the amount of vitamin D we can produce. You may opt to go in the sun for a short period of 10-15 minutes without sunscreen, and then apply sunscreen if you intend to spend more time in the sun. Of course, getting outdoors and exposing our skin to the sun on a daily basis becomes challenging if you’re not living in the tropics, so read on as we consider supplementation.
Understanding the Link Between Vitamin D and Brain Health
Let’s explore Vitamin D’s strong association with brain health. The presence of the Vitamin D Receptor (VDR) is prominent throughout the central nervous system, indicating an important role for vitamin D in the brain. In particular, the VDR is present in key cognitive areas like the hippocampus, cortex, and substantia nigra which are involved in memory, neuron vitality, and safeguarding cognitive health.4 In fact, studies looking at the association between vitamin D deficiency and cognitive decline have found that those moderately deficient in vitamin D have a 53% increased risk of dementia, and the risk increases by a drastic 125% if one is severely deficient. Relating to Alzheimer’s, one study found that those who were moderately deficient had a 69% increased risk, and the risk increased to 122% in those who were severely deficient.5 Some brain benefits of vitamin D include:
- Enhances activity of Nerve Growth Factor (NGF): NGF plays a key role in regulating a neural system involved in learning and memory. Vitamin D contributes to this process by activating NGF, allowing more NGF to support memory and learning mechanisms.4
- Reduces buildup of amyloid plaques: Vitamin D also supports the ability of immune cells in the brain to destroy amyloid proteins that become harmful plaques, which are classical hallmarks of Alzheimer’s disease. This helps clear the free proteins that are available and reduces the amount of amyloid plaque that builds up in the brain.4
- Activates detoxification pathways: Vitamin D supports detoxifying mechanisms in the brain by activating molecules that help remove toxins and by directly inhibiting some toxic compounds.4
- Regulates melatonin and other hormones: Vitamin D itself acts as a hormone and plays a role in regulating several other hormones. Vitamin D helps the body produce melatonin, which is important in regulating sleep, which is critical for cognitive health.6 Vitamin D can also help maintain the proper balance of numerous sex hormones.7
- Antioxidative protective mechanisms: Vitamin D has antioxidant properties, as it activates several pathways that reduce harmful compounds called free radicals.4
- Linked to reduced risk of age-related brain disease: Research suggests that higher intake of vitamin D is linked to a lower risk of Alzheimer’s Disease.8 Similarly, vitamin D intake is associated with a reduced risk of Parkinson’s Disease and better overall cognition in older adults.9,10
Factors to Consider When Choosing a Vitamin D Supplement
Vitamin D supplementation is a reasonable method of maintaining healthy vitamin D levels. Though, there are some important factors to consider when searching for the right vitamin D supplement. Vitamin D comes in two main forms, vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Cholecalciferol (D3) is the most “active” form of vitamin D and is generally considered the preferred form for a vitamin D supplement because it is more effective at increasing its blood levels.11
It is also important to consider the right dosage of a vitamin D supplement for you. Because vitamin D is a fat-soluble vitamin, it gets stored in fatty tissue, and having too much vitamin D can actually be harmful. According to the NIH, adequate serum vitamin D levels for overall health are generally considered between 20-50 ng/mL, while less than 12 ng/mL is considered vitamin D deficient.2 However, research suggests that even higher serum vitamin D levels are preferable for optimal health. For example, 32-100 ng/mL has been cited as healthy vitamin D levels, consistent with research finding people living in sunny regions are often in the range of 54-90 ng/mL.12 You can get your vitamin D levels checked through a simple blood test ordered by your primary care physician called serum 25-hydroxyvitamin D (25-OHD), and you can adjust your vitamin D supplement dosage depending on where you fall in the range. The NIH recommends daily vitamin D dosages of 600 IUs for adults and 800 IUs for older adults (over age 70).2 However, many supplements come in larger doses. If your vitamin D levels fall within a healthy range, 600-1000 IUs is often an appropriate dosage to maintain healthy vitamin D levels or increase them slightly. However, as we get older, a higher dose may be necessary to maintain healthy levels, so depending on your serum vitamin D levels, you may need to increase your dosage. Up to 2000 IUs is recommended to treat vitamin D deficiency, and even higher levels may be necessary for the elderly to obtain a healthy vitamin D serum range.13
Vitamin D is a crucial nutrient that helps support your health, especially your brain health. A great source of vitamin D3 is our nutritional supplement called RELEVATE, which contains cholecalciferol (D3), the most active form of vitamin D, sourced from Norwegian fisheries. The vitamin D3 in RELEVATE is dispersed in its native oil form, enabling more natural and enhanced absorption, unlike dry forms commonly found in capsule or tablet supplements. As mentioned, research also shows promising results in the use of vitamin D supplementation and associated decrease in the risk of diseases like Alzheimer’s and Parkinson’s. You can learn more about why we chose this form for our supplement by visiting here.
Remember, vitamin D is easy to neglect (think less time outdoors) and inadequately consumed in most people’s diets. So, stay fueled with enough vitamin D by spending more time outdoors with your skin exposed, eating more fatty fish, and supplementing with vitamin D3 as needed – and reap the benefits of a sharper mind and thriving body.
- Holick, M. F. Environmental factors that influence the cutaneous production of vitamin D. Am. J. Clin. Nutr. 61, 638S-645S (1995).
- NIH Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals. National Institutes of Health, Office of Dietary Supplements (2018). Available at: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/.
- Rhodes, L. E. et al. Recommended summer sunlight exposure levels can produce sufficient (≥20 ng ml-1) but Not the Proposed Optimal (≥32 ng ml-1) 25(OH)D levels at UK latitudes. J. Invest. Dermatol. 130, 1411–1418 (2010).
- Banerjee, A. et al. Vitamin D and Alzheimer’s Disease: Neurocognition to Therapeutics. Int. J. Alzheimers. Dis. 2015, 1–11 (2015).
- Miller, J. W. et al. Vitamin D Status and Rates of Cognitive Decline in a Multiethnic Cohort of Older Adults. JAMA Neurol. 72, 1295–1303 (2015).
- Romano, F. et al. Vitamin D and Sleep Regulation: Is there a Role for Vitamin D? Current Pharmaceutical Design 26, 2492–2496 (2020).
- Chu, C. et al. Relationship Between Vitamin D and Hormones Important for Human Fertility in Reproductive-Aged Women. Front. Endocrinol. (Lausanne). 12, 1–8 (2021).
- Annweiler, C. et al. Higher Vitamin D Dietary Intake Is Associated With Lower Risk of Alzheimer’s Disease: A 7-Year Follow-up. Journals Gerontol. Ser. A Biol. Sci. Med. Sci. 67, 1205–1211 (2012).
- Zhu, D. et al. Inverse associations of outdoor activity and vitamin D intake with the risk of Parkinson’s disease. J. Zhejiang Univ. Sci. B 15, 923–927 (2014).
- Annweiler, C. et al. Association of vitamin D deficiency with cognitive impairment in older women. Neurology 74, 27–32 (2010).
- Tripkovic, L. et al. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr 1357–1364 (2012). doi:10.3945/ajcn.111.031070.1
- Grant, W. B. & Holick, M. F. Benefits and Requirements of Vitamin D for Optimal Health: A Review. Altern. Med. Rev. 10, 94–111 (2005).
- Kennel, K. A., Drake, M. T. & Hurley, D. L. Vitamin D deficiency in adults: When to test and how to treat. Mayo Clin. Proc. 85, 752–758 (2010).