10 Nutritional Deficiencies That May Cause Depression

By Therese Borchard

Published Nov 14, 2014

I’m not sure why more psychiatrists don’t first test for nutritional deficiencies before dispensing Zoloft or Prozac, and especially antipsychotics like Seroquel and Zyprexa. The good ones will send you to get lab work done before upping your meds or adjusting anything. Sometimes we do need antidepressants. But other times we need spinach — think of Popeye.

In addition to seeing a psychiatrist regularly, I now work with an integrative health physician who tests my nutrition levels every year. If you haven’t ever tested your nutrition levels, you might inquire with either your psychiatrist or primary-care physician. The supplements can be expensive, but you can make it back two- or threefold by not having to see your psychiatrist as often. You should talk to your doctor before taking any supplements, especially if you’re on prescription drugs.

1. Omega-3 Fatty Acids

I was surprised when my results showed an omega-3 fatty acid deficiency because I eat plenty of salmon and take fish oil supplements every day. That shows you just how much fish — salmon, tuna, halibut — or flaxseeds and walnuts we need to consume to be at an optimal level. These essential minerals reduce inflammation and play a critical role in brain function, especially memory and mood. The body can’t make them, so you need to either eat them or take supplements. Omega-3 fatty acids are just one of the supplements I take every day for depression. 

2. Vitamin D

According to Mark Hyman, MD, bestselling author of The Ultramind Solution, vitamin D deficiency is a major epidemic that doctors and public health officials are just beginning to recognize. This deficiency has been linked to depression, dementia, and autism. Most of our levels drop off during the fall and winter months, since sunlight is the richest source. Dr. Hyman believes that we should ideally be getting 5,000 to 10,000 IU (international units) a day.However, the National Institutes of Health (NIH) recommends most healthy adults get only about 600 IUs daily.

3. Magnesium

Chances are good that you are magnesium-deficient because up to half of Americans are. Our lifestyles decrease our levels: excess alcohol, salt, coffee, sugar, phosphoric acid (in soda), chronic stress, antibiotics, and diuretics (water pills). Magnesium is sometimes referred to as the stress antidote, the “most powerful relaxation mineral that exists,” according to Hyman. It is found in seaweed, greens, and beans. The NIH recommends a daily intake of about 400 to 420 milligrams (mg) of magnesium for adult men and 310 to 320 mg for adult women.

4. Vitamin B Complex

B vitamins like vitamin B-6 and vitamin B-12 can provide some incredible health benefits, including reduced stroke risk and healthy skin and nails. On the other hand, a vitamin B deficiency may impact your mental health. More than a quarter of severely depressed older women were deficient in B-12, according to one 2009 study.

The best sources of vitamin B-6 are poultry, seafood, bananas, and leafy green vegetables. For vitamin B-6, the NIH recommends a daily intake of 1.7 mg for adult men, and 1.5 mg for adult women. Vitamin B-12 is found in animal foods (meat, fish, poultry, eggs, and milk) and shellfish, such as clams, mussels, and crab. Most adults should need to consume 2.4 micrograms (mcg) of vitamin B-12 daily, according to the NIH.

5. Folate

People with a low folate level have only a 7 percent response to treatment with antidepressants. Those with high folate levels have a response of 44 percent, according to Hyman. That is why many psychiatrists are now prescribing a folate called Deplin to treat depression and improve the effectiveness of an antidepressant. I tried it and it didn’t seem to make that much of a difference; however, I have several friends who have had very positive responses to Deplin. You need not try the prescription form of Deplin. You could just start taking a folate supplement and see if you get any results. Your daily recommended folate intake depends on your gender, whether you’re pregnant or breastfeeding, and age. However, most adults need at least 400 mcg daily. You can also get your daily folate requirements by consuming foods high in folate, including dark leafy greens, beans and legumes, and citrus fruits and juices.

6. Amino Acids

Amino acids — the building blocks of protein — help your brain properly function. A deficiency in amino acids may cause you to feel sluggish, foggy, unfocused, and depressed. Good sources of amino acids include beef, eggs, fish, beans, seeds, and nuts.

7. Iron

Iron deficiency is pretty common in women. About 20 percent of women, and 50 percent of pregnant women, are in the club. Only three percent of men are iron deficient. The most common form of anemia — an insufficient number of red blood cells — is caused by iron deficiency. Its symptoms are similar to depression: fatigue, irritability, brain fog. Most adults should consume 8 to 18 mg of iron daily, depending on age, gender, and diet, according to the NIH. Good sources of iron include red meat, fish, and poultry. If you really want to get more red blood cells, eat liver. Yuck.  

8. Zinc

Zinc is used by more enzymes (and we have over 300) than any other mineral. It is crucial to many of our systems. It activates our digestive enzymes so that we can break down our food, and works to prevent food allergies (which, in turn, averts depression in some people, since some of our mood disruptions are triggered by food allergies). It also helps our DNA to repair and produce proteins. Finally, zinc helps control inflammation and boosts our immune system. The NIH recommends a daily intake of 11 mg of zinc for adult men and 8 mg for adult women.

9. Iodine

Iodine deficiency can be a big problem because iodine is critical for the thyroid to work as it should, and the thyroid affects more than you think: your energy, metabolism, body temperature, growth, immune function, and brain performance (concentration, memory, and more). When it’s not functioning properly, you can feel very depressed, among other things. You can get iodine by using an iodine-enriched salt, or by eating dried seaweed, shrimp, or cod. I take a kelp supplement every morning because I have hypothyroidism. The daily recommend amount of iodine for most adults is about 150 mcg.

10. Selenium

Like iodine, selenium is important for good thyroid function. It assists the conversion of inactive thyroid hormone T4 to the active thyroid hormone, T3. It also helps one of our important antioxidants (glutathione peroxidase) keep polyunsaturated acids in our cell membranes from getting oxidized (rancid). Most adults need about 55 mcg of selenium daily. The best food source of selenium is Brazil nuts, which contains about 544 mcg of selenium per ounce.