Seasonal Affective Disorder: What Vitamins Should You Take?

What is seasonal affective disorder?

Seasonal affective disorder (SAD) is a condition often referred to as the ‘winter blues.’ It consists of depressive episodes occurring at similar times each year. 

For most cases, it occurs in the colder, winter months when sunlight levels are reduced. It differs from regular depression as symptoms ease during the summer months. 

The condition affects about 1%–2% of the US general population, although women experience it at a higher ratio than men – approximately 4:1. 

It’s a critical mental health issue, making up approximately 11%¹ of all cases of depression.

Symptoms of seasonal affective disorder

Common symptoms of SAD include: 

• A decrease in pleasure or interest for activities that you previously enjoyed

• Withdrawal from social activities

• Feeling sluggish or increasingly tired

• A sense of worthlessness or hopelessness

• Difficulties in concentration

• Repeated thoughts of death or dying

• Feelings of guilt

SAD varies in severity from one person to another based on personal and environmental factors. In many cases, it can be severe and can impact different areas of a person’s life.

Treating seasonal depression

Early treatment can reduce the chances of the disorder becoming worse and improve your quality of life. Several therapies have been shown to be effective. These treatments include:

• Counseling

• Light therapy

• Sun exposure

• Vitamin supplementation

Vitamin supplementation is useful in treating the underlying cause and supporting other treatments. This is because, in addition to other biological and environmental risk factors, a deficiency in certain vitamins is a potential trigger for seasonal depression.

How can vitamins help with seasonal affective disorder?

Some vitamins regulate biochemical pathways in the brain, assisting proper cognitive functioning. Since SAD is a mental disorder, ensuring proper levels of vitamins could be highly beneficial. 

Nutritional imbalances are among the influencing factors² of depression. Correcting these could reduce symptoms and improve moods in people with SAD. 

You can do this through your diet. However, many factors influence your ability to get the required amount of certain micronutrients, including:

• Bioavailability (the ability of a substance to be absorbed and used by the body)

• Gut health

• Proper functioning of other bodily processes

For most people, a balanced diet rich in whole foods is enough to maintain levels of particular vitamins. 

However, some people are more likely to develop SAD or depression due to genetic, biological, or environmental factors. If these people have even mild deficiencies of certain nutrients, their symptoms could be triggered or made worse. 

Those severely lacking are at a higher risk, so supplements of vitamins and other nutrients could be beneficial.

How to ensure safe and effective use of vitamins

Although vitamins can be beneficial in some cases, consumption comes with risks. You can take most over-the-counter supplements at low doses without any major issues. 

However, to fix deficiencies, higher doses may be required. In this case, treatment should be conducted under medical supervision. 

Testing blood levels is also important to ensure that you are indeed deficient. 

Seeking proper medical supervision when taking supplements for a disorder can help to ensure a safe and effective treatment plan. 

Medical professionals or naturopathic doctors can support patients with the following:

• Verifying accurate vitamin levels with blood tests

• Administering the correct dosage

• Monitoring symptoms for improvement or deterioration

• Testing to determine whether certain supplements are well tolerated

• Regular testing of vitamin levels to determine if the vitamin dosage should change

Vitamin supplements should not replace a healthy diet but can support it when taken correctly. 

Vitamins and how they function in seasonal affective disorder

Vitamins can be a great way for some people affected by SAD to treat seasonal fluctuations in mood. They are easily accessible, natural, and cost-effective. 

Brain processes rely on micronutrients, such as vitamins to produce energy and neurotransmitters.

Neurotransmitters are responsible for transferring information between nerve cells in the brain to produce specific responses, such as changes in emotions. 

Since symptoms of SAD are similar to depression, vitamins that are useful in treating people with normal depression may help. 

Research has shown that the following vitamins may play a role in helping SAD:

Vitamin D

Vitamin D is possibly the most studied vitamin for the treatment of SAD, and it’s an essential hormone for bodily processes, especially mood management. 

Vitamin D appears to play an important role in SAD since levels drop during the winter as sun exposure decreases. Evidence shows that supplementing vitamin D relieves³ SAD symptoms but only when you have below-normal levels. 

Because vitamin D is stored in the body, getting enough of it during the summer could help reduce the chances of symptoms occurring during the winter. 

One study demonstrated that taking 5,000iu of vitamin D⁴ per day helped reduce symptoms of SAD. 

However, other research⁵ has not found vitamin D supplementation helps reduce symptoms of seasonal depression. 

How to take vitamin D

Supplements can be purchased over the counter or prescribed in higher doses from a clinician. 

Since vitamin D is a fat-soluble vitamin, you should take it with your largest meal of the day. 

Note that taking above 40,000iu (1,000 micrograms) per day can result in vitamin D toxicity.

B vitamins

B vitamins are involved in many brain processes such as:

• Energy metabolism

• Production of neurotransmitters

• Healthy nerve cells

They are found in foods such as:

• Vegetables (especially leafy greens)

• Whole grains

• Eggs

• Fruit

• Fish

• Liver

• Other animal proteins

You can get a full range of the different B vitamins via B-complex supplements. 

However, the different B vitamins have different properties and effects on the body. So, it might be worth considering each B vitamin separately and only taking the required ones. 

In particular, B1, B3, B6, B9, and B12 are essential in cognitive functioning⁶, and shortages in the following B vitamins are associated with depression:

Vitamin B12 (cyanocobalamin)

B12 plays a vital role in brain functioning, and research also shows that below-normal levels of B12⁷ are linked to experiencing depression symptoms.  

B12 is commonly found in animal products, so vegetarians and vegans can find it difficult to get enough through their diet. 

Supplementing B12 levels has been shown to relieve symptoms⁸ in people with depression. 

Vitamin B6 (pyridoxine)

B6 affects neurotransmitters, the chemical messengers in the brain, which impact depression. It plays a role in controlling moods and mental functioning. 

Low blood levels of B6 have been linked to the development of depression symptoms.

Vitamin B9 (folic acid)

B9 is abundant in plant foods and plays a role in DNA repair. Many studies⁹ have found a link between low folate levels and depressive symptoms. 

Folic acid plays an important role in producing serotonin (an important hormone that affects mood).

You can lack B vitamins because of your diet or from consuming excess caffeine or alcohol. Some medications may also impact the absorption of B vitamins in the body. 

Omega-3 fatty acids

These are primarily found in fish oil. The two most effective forms for improving mood are EPA and DHA. 

Research¹⁰ has found that doses between 1g and 2g per day, with at least 60% EPA relative to DHA, help treat symptoms of depression.

Sam-E (S-adenosylmethionine)

Sam-E is a naturally occurring molecule in the body. It can be as effective as some antidepressants¹¹ but has mild side effects.

Sam-E is involved in regulating neurotransmitters and communication between nerve cells in the brain. It may also impact our behavior and thoughts, which may be affected in people with depression.

Many other vitamins could help treat SAD, but further research is needed.

Risks and precautions of taking vitamins

Some vitamins shouldn’t be taken while pregnant or breastfeeding. Others can be toxic at high doses, and you should avoid some supplements if you have certain medical conditions.

Some methods of taking vitamins boost absorption, so seeking medical advice is highly recommended before you start taking supplements.

For example, you should not take some vitamins together as they can prevent each other from being properly used by the body.

It is crucial to discuss the supplements you plan to take with your physician, especially if you are pregnant or suffer from a chronic medical condition or mental health issue.

The lowdown

Vitamins can help people cope with SAD as long as they are both safe and effective at reducing depression symptoms and improving general well-being.

Vitamins can also be used as a preventative measure for SAD to help reduce the chances of symptoms occurring.

Always consult a medical practitioner for advice on which vitamins may be best for you.