Vitamin D is a fat-soluble vitamin well-known for its supportive role in bone health and immune function. Research indicates that vitamin D can influence every body system. Vitamin D receptors (VDRs) are found in most tissues throughout the human body including the brain. Vitamin D has been shown to help support many biochemical processes linked to aging, including antioxidative status, a healthy inflammatory response, cell signaling, and telomere integrity. It can also help support autophagy and the health of DNA and mitochondria. Deficiencies in vitamin D status have been linked to certain age-related illnesses. Recent research suggests that vitamin D supplementation may help promote cellular health and healthy aging. 

The body’s ability to process vitamin D decreases during aging. When compared to younger adults, elderly individuals have been shown to experience 50% reductions in the skin’s ability to convert vitamin D to its bioactive form. Several animal studies in VDR knockout mice have reported premature aging, a shorter life span, and the incidence of age-related illnesses such as osteoporosis, immune deficiencies, alopecia, and muscle atrophy.  

Many age-related illnesses are associated with changes to the central nervous system and brain. Vitamin D has been shown in studies to support neuronal health through its ability to help attenuate oxidative stress and support a normal inflammatory response. It may also help promote healthy levels of certain neurotrophins, including the synthesis of the nerve growth factor, glial cell line-derived neurotrophic factor, and neurotrophin 3.  

A 6-year clinical study involving elderly individuals reported an association between lowered vitamin D status and cognitive decline. Polymorphisms in VDRs have been linked to cognitive decline and certain neurodegenerative diseases such as Parkinson’s disease. A study involving more than 500 individuals who were 85 years of age reported the presence of cognitive differences among participants that correlated with VDR polymorphisms. An animal study involving Alzheimer’s disease indicated that vitamin D administration helped support neurogenesis and improvements in cognition. Further clinical studies need to be conducted before conclusions can be made.  

Deficiencies in vitamin D are common in adult populations. Vitamin D can be obtained from sun exposure, supplementation, and dietary sources such as fatty fish (including salmon), beef liver, egg yolks, mushrooms, and fortified foods. Cholecalciferol, also known as vitamin D3, is the most active form of supplemental vitamin D. Evidence suggests that supplementation with vitamin D3 can be more effective at raising and maintaining vitamin D levels in the body rather than vitamin D2. 

Research suggests that vitamin D may promote health in many systems of the body. Vitamin D may also support cellular health, neuronal function, and healthy aging.  

By Colleen Ambrose, ND, MAT