Vitamin D is the main hormone that regulates the homeostasis of phosphorus and calcium. The discovery that a variety of tissues can express the vitamin D receptor has opened new avenues of research concerning the biological effects and molecular pathways of vitamin D.
In addition to its effects on bone metabolism, vitamin D also appears to be involved in the regulation of the immune system, the cardiovascular system, and cognitive functions.
Muscle loss and weakness are common in many chronic diseases, such as chronic obstructive pulmonary disease, heart failure, cancer, and chronic kidney disease; What are the diseases that suffer, especially our elders. In fact, vitamin D deficiency is extremely common in the above diseases.
From where do we get Vitamin D?
The skin, liver and kidneys are involved in the metabolism of vitamin D. The role of sun exposure is important, as UVB-stimulated vitamin D3 production in the skin accounts for 80 to 90% of vitamin D formation, whereas nutrient intake accounts for only 10 to 20% of the vitamin D3 contribution Is.
Within a variety of foods, vitamin D, which is a fat-soluble vitamin, is found in high concentrations in fish, and those with the greatest contribution of this micronutrient are those that are blue or have a high lipid content.
The egg is also a source of vitamin D, but it concentrates most of this micronutrient in the yolk, which is provided by the fat portion. Thus, we can use both egg yolk alone and whole eggs if we want to add fat as well; Proteins that provide satiety.
Vitamin D and muscle strength
25-Hydroxyvitamin D is used as a marker of vitamin D status, and low serum vitamin D (25-hydroxyvitamin D) levels can define vitamin D deficiency versus insufficiency.
However, definitions of low vitamin D levels vary between authors and nutritional societies/authorities. Vitamin D deficiency can be defined as the level below which a hormone, PTH, begins to rise and depending on the studies, this level can range from 25 to 75 nmol/L.
Several studies have investigated the clinical relationship between serum vitamin D concentration and physical performance and quality of life in the elderly. For example, the Invecchiare in Chianti study, involving 966 individuals with an average age of 75 years, found a significant association between low levels of vitamin D and poor physical performance as assessed by the handgrip strength test.
Additionally, those with serum vitamin D levels below 25 nmol/L fared worse than those with levels above 25 nmol/L. Muscle strength using the grip test was also significantly higher in subjects with vitamin D levels greater than 50 nmol/L compared to those with levels below this threshold.
Another study reported that in healthy women over the age of 65, vitamin D levels greater than 50 nmol/L were associated with increased lower extremity muscle strength.
Does Vitamin D Help With Muscle and Strength Gains?
In this study, both the elderly and the youth were offered 2,000 IU of vitamin D3. At the end of the study, although the younger people did not have any improvement in muscle quality, the older people did.
Initially it was thought that there was no link between vitamin D deficiency and the risk of fractures or falls, but current understanding has highlighted the importance of direct effects of vitamin D on muscle strength and function.
In fact, the most recent report from the Endocrine Society Clinical Practice Guidelines recommends vitamin D supplementation according to age and clinical circumstances, especially to prevent decline in populations at risk.
That is why, if our elders are unable to get a lot of sunlight due to the fragility of their skin, it is best to supplement with foods rich in fats such as olive oil, nuts, etc. so that it gets absorbed properly. Also, the supplement dosage should be specified by the doctor.