Seasonal Affective Disorder, or S.A.D., is a name the medical industry has given to the depression many people feel in the winter time. Of course, depression can have multiple causes, but if you notice yourself feeling down more in the winter than in any other season, or just so than normal, there’s a good chance it’s S.A.D. more than anything else.
But the name itself is a bit of misnomer. It’s not a disorder in any way, but the result of a lack of sufficient sun exposure, which is why it tends to strike in the winter rather than the summer. Those with darker skin are even more susceptible because they require more sun exposure to receive adequate “sunlight nutrition.”
So what is it you exactly need from the sun? The sun provides two major benefits. The first is vitamin D3, and the second is full-spectrum light. Both are more or less replaceable in non-sunlight forms, and so both should be, since it’s common for people either to seek antidepressant drugs or only address one of the two deficiencies, resulting in only a partial cure. Addressing both aspects can help you not only avoid or cure winter-time depression, but improve your immunity and overall physical health as well.
The first step, vitamin D3, is actually not a vitamin but a hormone. However, it’s so critical for proper health that studies show that sufficient and regular vitamin D3 intake alone can prevent up to 77% of all cancers. Moreover, it’s often pointed to as the primary nutritional reason people tend to get sick in the winter. To ensure your body has enough vitamin D3, unless you have reason to believe you have sufficient level already, you’ll need to supplement with it in heavy doses for two to three months to raise the amount of vitamin D3 in your blood on a general, sustained level. This means 40,000IU to 50,000IU per day for most adults, before tapering down to 7,000IU to 10,000IU per day depending on body weight. People with darker skin may benefit from taking a slightly larger amount, since the nutrients from sunlight have more difficulty penetrating darker skin. This larger amount could be anywhere from 10% to 30% more depending on skin tone.
The second step, full-spectrum light, is light in its most natural form—the light the sun provides. Full-spectrum light has every wavelength of light in the electromagnetic spectrum, so it has every band of light needed to support life in plants and animals. Ideally, all your indoor lighting should be sourced by full-spectrum light, since you can buy these light bulbs for nearly the same cost as artificial forms of light. Artificial light, like fluorescent light, has only a fraction of the wavelengths of sunlight, and constant exposure over time can dull your mood, cause difficulty concentrating, and even lead to depression, regardless of the season. The simplest way to get full-spectrum light exposure is to spend time out in the sun—for light-skinned people, that can be as little as 15 minutes a day, and for very dark-skinned people, 30 to 35 minutes a day. But when that’s difficult to do, especially in very cold weather, you can buy a small full-spectrum light stand for a fairly low cost. Because it mimics sunlight on the body, the 15 to 35 minute per day guideline, based on skin tone, is enough to noticeably bring about a change in general mood.