Vitamin D – sources, benefits and dosage

Curious if you’re receiving enough of this required vitamin by soaking up some healthy sun rays, or do you need help from a supplement?

What does vitamin D do for our body, and how does it help our healthspan?

What is vitamin D?

Vitamin D assists in regulating the amount of calcium and phosphate in the body as these nutrients are needed to maintain muscles, bones and teeth in top shape [1]. Health practitioners advise everyone to consider taking a daily vitamin D supplement during the autumn and winter.

What are good sources of vitamin D?

From around late March to early April until the end of September, most people should be receiving the vitamin D they need from sunlight. The body forms vitamin D from direct sunlight on the skin when outdoors. However, between October and early March (in the Northern Hemisphere), we do not make enough vitamin D from sunlight.

Vitamin D is in foods sources such as:

  • Egg yolks
  • Fortified foods: breakfast cereals and some fat spreads 
  • Liver
  • Oily fish: like herring, mackerel, salmon and sardines 
  • Red meat
From around late March to early April until the end of September, most people individuals should be receiving the vitamin D they need from sunlight.

Why do I require vitamin D and how do I get it?

How to check if you’re receiving enough vitamin D? A deficiency of this vitamin can lead to bone deformities (bone pain caused by a condition called osteomalacia in adults and rickets in children ). Now, look into why you’re not getting enough vitamin D to stay healthy [2].

Vitamin D assists the body in calcium absorption – one of the main building blocks of bones. Likewise, it has a role in your immune, muscle, and nervous systems.

You can get it through: 

  • Diet 
  • Your skin
  • Supplements

Your body forms vitamin D innately after exposure to sunlight. But be wary that too much sun exposure may develop into skin aging and even skin cancer – this is why so many people try to get their vitamin D from other sources.

Featured product offer
Double Wood Supplements Vitamin D3 + K2 Liquid Drops
  • Contains trans-K2 to prevent hypercalcemia from high-dose D3 supplementation.
  • Gluten-free, soy-free, non-GMO, vegan.
  • Made in the US at a cGMP certified facility.

What are the benefits of taking vitamin D daily?

There’s more to vitamin D than it’s given credit for. Here are some awesome benefits:

  • Can aid in weight loss: consider raising your levels of vitamin D3 through diet and sunlight exposure. Studies found that eating more foods that are rich in this vitamin. Taking a vitamin D3 supplement, or simply getting more sun – plus a balanced diet and exercise, can make it more manageable to lose weight.
  • Decreases risk of type 2 diabetes: if diabetes runs in the family or you have been hyperglycemia or pre-diabetes, you might want to look into getting more vitamin D. Studies confirm that the connection between the body’s resistance to insulin, vitamin D deficiency and type 2 diabetes. By overcoming insulin resistance, you could prevent the development of type 2 diabetes.
Can aid in weight loss: consider raising your levels of Vitamin D3 through diet and sunlight exposure
  • Elevates your mood: vitamin D helps your daily mood, particularly in the colder, darker months. Several studies have indicated that the symptoms of Seasonal Affective Disorder (SAD) may be connected to low levels of vitamin D3 – associated with the lack of sunlight exposure.
  • Helps lower blood pressure: several long-term studies have demonstrated a linkage between low vitamin D levels and hypertension or high blood pressure.

Until recently, it wasn’t unknown if being deficient in vitamin D leads to hypertension, but a sizeable genetic study involving more than 150,000 people revealed that low levels of vitamin D could cause hypertension.

  • Low risk of rheumatoid arthritis: studies have found that people with rheumatoid arthritis (a chronic inflammatory disease of the joints) often have low levels of vitamin D. Rheumatoid arthritis is an autoimmune disease – where the immune system reacts to the linings of the joints as if these proteins were foreign substances. This leads to joint inflammation resulting in stiffness, pain and reduced mobility.
  • May improve brain function: vitamin D has been connected with numerous vital bodily functions, including how the brain functions. There are vitamin D receptors throughout the brain and the spinal cord. Vitamin D benefits you by playing a role in activating and deactivating neurotransmitters synthesis, as well as nerve growth and repair. Also, studies on animal subjects found that vitamin D helps to protect neurons and can reduce inflammation within the brain. 
  • Might reduce risk of heart disease: an increasing number of studies have exhibited that a deficiency in vitamin D is one risk factor for developing congestive heart failure, high blood pressure, heart disease, peripheral arterial disease, heart attack and strokes. Improving vitamin D levels can help reduce heart disease risk and symptoms that are associated with it.
  • Might prevent certain types of cancer: vitamin D3 helps control the development of some types of cancer. Epidemiologic research showed that there is a descending incidence of certain types of cancers for individuals who living in the southern/equatorial locations and have more exposure to the sun.

Several experiments have shown that there is a probable connection between vitamin D and cancer development. The vitamin aids in the repair and regeneration of cells, which could lessen the growth of cancerous tumours, stimulate the death of cells that have been damaged by cancer and lower the formation of blood vessels in tumours.

Featured product offer
Elm & Rye Vitamin D3
  • Available in capsules and gummies.
  • High levels of Vitamin D lead to leaner bodies, increased muscle mass, and better muscle function.
  • Contains Vitamin D and calcium that help maintain bone health.

Reinforces teeth and bones: vitamin D3 helps with the regulation and absorption of calcium, and it plays essentially in the health of your teeth and bones [3]. Calcium is the most abundant of all the minerals in the body and majority lies in the skeletal bones and teeth.

Strengthens immune system: one of the most critical vitamin D benefits is its role in maintaining and enhancing the immune system. It also stimulates production of T-cells and helps to promote a proper action to infectious pathogens, including: bacteria, viruses and fungus, that are responsible for various types of illnesses, including the common cold, influenza, and similar community-wide diseases. In addition, there is evidence that it helps reduce the severity and duration of COVID-19 [4]. 

Can you take too much vitamin D?

Looking into the recommended amounts we need, children from the age of one year are recommended 10 micrograms daily – this also includes pregnant and breastfeeding women, as well as people at risk of vitamin D deficiency. Babies up to the age of 1 require 8.5 to 10 micrograms of the vitamin a day.

A microgram is 1,000 times smaller than a milligram (mg) – it’s often written with the Greek symbol μ and followed by the letter g (μg). The amount of vitamin D is occasionally expressed as International Units (IU). 1 microgram of vitamin D is equivalent to 40 IU. So 10 micrograms of vitamin D is equivalent to 400 IU.

Can you take too much of it, though? Vitamin D supplements are regarded as very safe and toxicity is not common, as a a healthy person would need to take massive doses of vitamin D over time to reach toxic or dangerous levels in the body.

However, vitamin D toxicity is more typical in people with certain medical conditions. These include:

  • Congenital disorders
  • Dysregulated vitamin D metabolism
  • Granulomatous disorders
  • Some lymphomas

Although uncommon, vitamin D toxicity can happen, especially in cases of:

  • Accidental overdose
  • Misuse of high-dose vitamin D supplements
  • Prescription errors

Vitamin D toxicity comes under a few names, including hypervitaminosis D and vitamin D intoxication [5].

When is the best time to take vitamin D?

Vitamin D can be taken anytime. Nevertheless, many people prefer to take it in the morning to reduce the potential risk of sleep disruptions [6]. But did you know that it can matter when and what you take it with in terms of absorption?

There’s no required standard on the best time to take vitamin D, but some people choose to take their supplements earlier in the day with a meal. Others think that taking vitamin D before bed can interfere with sleep, though there’s no solid scientific evidence to back this up.

Should you take vitamin D with food?

Vitamin D is fat-soluble, so it dissolves in oils or fats. That’s why it’s best to take your supplement with foods that have healthy fats (such as olive oil, seeds, nuts, fatty fish, or eggs).

One question remains on whether it’s better to take vitamin D supplements with low-fat or high-fat foods. A study looked into 62 older adults who took a 50,000-IU vitamin D3 supplement once a month for three months. The participants were separated into three meal groups: no meal, high-fat meal and low-fat meal.

At the end of the study, researchers saw that the individuals who took vitamin D3 supplements with a low-fat meal had better absorption. Note that the study was small and more research is required on how the body can best absorb vitamin D.

For now, it’s an excellent suggestion to stick to adding the recommended foods to your diet, enjoying some safe sun time and taking supplements if necessary. 

Featured product offer
Global Healing Vitamin D3
  • Vegan formula for strong bones, immune support, and brain optimization with active vitamin D.
  • Made from organic lichen and has cholecalciferol, the active form of vitamin D produced by sunlight.
  • Gives 5,000 IU per serving.


The information included in this article is for informational purposes only. The purpose of this webpage is to promote broad consumer understanding and knowledge of various health topics. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.