My recent blood test revealed a “moderate vitamin D deficiency”. I have been taking a Voost multivitamin supplement about 5x per week. This multivitamin has 200IU of Vitamin D. My GP told me to take another 1000IU per day.
I’m taking a Swisse D3 as colecalciferol. 1000IU is about 25 micrograms. It’s a pretty small capsule.
What is Vitamin D?
Vitamin D is important for strong bones, muscles and overall health. Ultraviolet (UV) radiation from the sun is necessary for the production of vitamin D in the skin and is the best natural source of vitamin D.
We also know that UV radiation from the sun is the main cause of skin cancer. So we need to be careful especially white boys like me.
Small amounts of the vitamin D you need can be obtained through food (about 5 – 10 per cent). Fish and eggs naturally have some vitamin D, while margarine and some milks have added vitamin D.
The body can only absorb a limited amount of vitamin D at a time. Spending extra time in the sun will not increase vitamin D levels – but will increase your risk of skin cancer.
Daily exercise also assists with the body’s production of vitamin D.
Health effects of low vitamin D
Vitamin D deficiency does not always have obvious symptoms but without treatment there can be significant health effects. These can include bone and muscle pain, and softening of the bones – such as rickets (in children) and osteomalacia (in adults).
Some people are at greater risk of vitamin D deficiency, including:
- people with naturally very dark skin –this is because the pigment (melanin) in dark skin doesn’t absorb as much UV radiation
- people who avoid the sun due to previous skin cancers, immune suppression or sensitive skin and those people who have limited sun exposure, such as nightshift workers
- people who wear covering clothing or concealing clothing
- people who spend a long time indoors – such as those who are housebound or institutionalised
- people who are obese
- people who have a disability or a disease that affects vitamin D metabolism, such as end stage liver disease, renal disease and fat malabsorption syndromes such as cystic fibrosis, coeliac disease and inflammatory bowel disease
- people who take medication that affects vitamin D metabolism
- breast-fed babies of vitamin D deficient mothers (formula milk is fortified with vitamin D)
Overexposure to UV is never recommended, even for people who have vitamin D deficiency.
Vitamin D and food
There are small amounts of vitamin D in some foods such as fish, eggs and UV-irradiated mushrooms, but it is difficult to obtain enough vitamin D from diet alone. Most people only get five to 10 per cent of their vitamin D from food.
Vitamin D and safe sun exposure
UV levels vary depending on the time of year, and the amount of sun exposure you need varies accordingly.
The ‘daily sun protection times’ indicate when the UV level is forecast to be three or above. During these times, people are recommended to use a combination of sun protection measures (sunscreen, hat, protective clothing, sunglasses and shade).
Check the free SunSmart app or the Bureau of Meteorology website for daily sun protection times for your location.
Vitamin D may fight disease
In addition to its primary benefits, research suggests that vitamin D may also play a role in:
- Reducing the risk of multiple sclerosis (MS). A 2018 review of population-based studies found that low levels of vitamin D are linked with an increased risk of MS (2).
- Decreasing the chance of heart disease. Low vitamin D levels have been linked to increased risk of heart diseases such as hypertension, heart failure, and stroke. But it’s unclear whether vitamin D deficiency contributes to heart disease or simply indicates poor health when you have a chronic condition (3).
- Reducing the likelihood of severe illnesses. Although studies are mixed, vitamin D may make severe flu and COVID-19 infections less likely. A recent review found that low vitamin D levels contribute to acute respiratory distress syndrome (4, 5).
- Supporting immune health. People who do not have adequate vitamin D levels might be at increased risk of infections and autoimmune diseases, such as rheumatoid arthritis, type 1 diabetes, and inflammatory bowel disease (6).
Vitamin D may regulate mood and reduce depression
Research has shown that vitamin D might play an important role in regulating mood and decreasing the risk of depression.
A review of 7,534 people found that those experiencing negative emotions who received vitamin D supplements noticed an improvement in symptoms. Vitamin D supplementation may help people with depression who also have a vitamin D deficiency (7).
Another study identified low vitamin D levels as a risk factor for more severe fibromyalgia symptoms, anxiety, and depression (8).
It might support weight loss
People with higher body weights have a greater chance of low vitamin D levels (9).
In one study, people with obesity who received vitamin D supplements in addition to following a weight loss diet plan lost more weight and fat mass than the members of the placebo group, who only followed the diet plan (9).
In an older study, people taking daily calcium and vitamin D supplements lost more weight than subjects taking a placebo supplement. The researchers suggest that the extra calcium and vitamin D may have had an appetite-suppressing effect (10).
The current research doesn’t support the idea that vitamin D would cause weight loss, but there appears to be a relationship between vitamin D and weight.
Risks of getting too much vitamin D
If you take excessive amounts of vitamin D supplements, you may get too much of it. However, this is unlikely to happen through diet or sun exposure because your body regulates the amount of vitamin D produced through sun exposure.
Vitamin D toxicity can lead to an increase in your blood calcium levels. This can result in a variety of health issues, such as (11):
- nausea
- apathy
- vomiting
- abdominal pain
- dehydration
- confusion
- increased thirst
It’s pretty important to work through your vitamin D levels with your GP and getting a blood test to actually see what your current levels are.
