Numerous studies have linked vitamin D to depression. When we don’t get enough vitamin D, we are at greater risk of depression. One of the most supportive connections is a recent study in the Netherlands involving over 2000 adults aged 18-65, which found a strong link between vitamin D and depression. In fact, what they found was a consistent relationship between the amount of vitamin D in the blood and severity of depressive symptoms. So, a mild deficiency was consistent with mild depression and severe deficiency was consistent with severe depression. Similarly, researchers from the University of Antwerp in Belgium looked at depression and vitamin D levels in 589 elderly nursing home residents. “Almost our entire study population appeared to be vitamin D deficient. Comparison of the most severely and least deficient subgroups showed a consistent tendency towards more depressive symptoms and more use of antidepressants in the group with the lowest vitamin D level”.
VITAMIN D AS TREATMENT FOR DEPRESSION
An encouraging experiment at the Tehran University of Medical Sciences in Iran compared the therapeutic effects of treating depression with fluoxetine (Prozac) alone or with a combination of fluoxetine and vitamin D. In the double-blind, randomized, placebo controlled study, involving 42 patients over a period of 8 weeks, they found that treatment with fluoxetine combined with vitamin D was superior to treatment with fluoxetine alone. So, this is good evidence that vitamin D can enhance traditional pharmaceutical treatment of depression.
Enough information is currently available to make us reasonably confident that there is a connection between vitamin D and depression. What we don’t know for sure is that low levels of vitamin D cause depression. We know that depressed people tend to have low levels of vitamin D and non-depressed people tend to have higher levels of vitamin D. And there is good evidence from the recent Tehran University of Medical Sciences study that vitamin D has a positive effect when used to treat depression, at least in conjunction with a traditional anti-depressant. What this tells me is that vitamin D is something that should be considered when we are talking about preventing and treating depression. I am confident that many more studies will be forthcoming soon that will settle the question of causality and demonstrate how vitamin D may be used to treat depression alone, or in conjunction with other nutrients. Meanwhile, it makes sense, given the evidence regarding the association between vitamin D and depression, to maintain adequate levels of vitamin D.
VITAMIN D FROM THE SUN
This comes with some good news and some bad news. The bad news is that it is very difficult to get enough vitamin D from food alone. This is why vitamin D is added to a number of foods including milk, soymilk and fortified cereals. About the only things vitamin D occurs in naturally are fatty fish like salmon, sardines, and tuna, eggs, and mushrooms. Some mushrooms are higher in vitamin D than others. It depends on how they were grown and if they were exposed to sunlight. Mushrooms convert sunshine or UVB rays to vitamin D like we do. Which brings me to the good news; our main source of vitamin D is the sun! We convert ultraviolet B (UVB) rays from the sun to vitamin D through our skin. The bad news here is that if you live north of 42 degrees latitude, as I do in Montana, the angle and distance of the sun make it impossible to get enough UVB rays from November to March. The 42nd parallel is the southern border of both Oregon and Idaho and runs through the states of Wyoming, Nebraska, Iowa, Illinois, Michigan, Pennsylvania, New York, Connecticut, Rhode Island, and Massachusetts.
South of the 42nd parallel year-round and north of the 42nd parallel from March through October, the amount of vitamin D you will get from the sun will depend on several things. More UVB rays are available in the middle of the day than they are in the morning or evening. Lighter skinned people will absorb more UVB rays for conversion to vitamin D than dark skinned people in the same amount of exposure time. How much skin you have exposed will affect how much vitamin D you get from the sun. Clouds and air pollution can also block UVB rays.
Basically, a light skinned person with arms, legs, and face exposed to the sun (without sunscreen) in the middle of the day, will get about 10,000 units of vitamin D in about 10 minutes. That is very good news because you probably don’t need anywhere near that much vitamin D in one day. Darker skinned people need to be in the sun longer to absorb the same amount as light skinned people because the melanin in darker skin helps to block UVB rays. People of Hispanic origin, for instance, probably need to be in the sun nearly twice as long and very dark skinned people of African origin may need to be in the sun 6 times as long. Recommendations for vitamin D vary from the FDA’s Percent Daily Value (%DV) of 400 IU’s (International Units) per day for most people to prescription doses of 50,000 IU’s per week with an upper limit recommendation of 10,000 units per day. The Vitamin D Council recommends 5000 units per day.
TANNING BEDS
It is possible to get some vitamin D from tanning beds. How much you are able to get varies because tanning beds use lights with different rays and in different strengths from each other. Some tanning beds have stronger UVB rays than others. A very rough estimate would be 20%. So, 10 minutes in a tanning bed for a light skinned person might give you about 2000 units of vitamin D.
VITAMIN D, MAGNESIUM AND CALCIUM
The body needs vitamin D to absorb calcium. Without enough vitamin D, we can’t properly utilize calcium, which is also associated with both depression and anxiety. It is important to know if supplementing with vitamin D, that calcium and magnesium also work together and taking too much of one can create a deficiency in the other. So, taking a calcium supplement alone, which many people do, without also taking vitamin D and magnesium at the same time can cause a deficiency in magnesium while the calcium is not fully absorbed. No one nutrient works alone. Nature does a good job of providing everything we need if we eat a good variety of whole, natural foods. Our intake of vitamin D is something we need to be especially aware of if we live in a northern latitude. Eat foods containing vitamin D as much as possible in the winter including:
And soak up as much sun as you can before November!
Please don’t forget to mention that thirty minutes in the early morning and thirty minutes during sunset are the best timesto get some vitamin D and K though very hard to get during our weather months. Thank you for this info will keep up on your blog
Thanks for that Christina. You will actually get more vitamin D from the sun in the middle of the day when the UVB rays are the strongest. Vitamin K we don’t get from the sun. We convert bacteria in our intestines into vitamin K and some foods have vitamin K. Glad you are following!
I’m not sure the place you’re getting your info,
but good topic. I must spend some time learning much more or figuring out more.
Thank you for great info I was in search of this information for my mission.