I tried taking fish oil capsules, but they tasted fishy. Any suggestions?

First of all, if something tastes really bad, it's best to throw it out. Some fish oil preparations are more pure and better encapsulated than others, and you don't want to take any chances.

Some excellent products either have no taste or slight citrus flavorings. One other suggestion: keep the capsules in the refrigerator or freezer, because cold temperatures diminish the taste of many foods. Keeping these supplements cold may also help keep them fresh.

— Dr. Marlene P. Freeman, psychiatrist

Massachusetts General Hospital

What is maca root?

Maca root is a tuber (a plant, such as the potato, that grows underground) found in South America. In folk medicine, maca root is used as an aphrodisiac or to boost sexual performance.

At MGH, we have conducted two preliminary studies that suggest maca root extracts may boost libido, particularly in postmenopausal women. And we have anecdotal evidence from individual patients that maca root may also help counter the sexual side effects of antidepressants, such as reduced libido and difficulties having orgasm, in both men and women. The recommended dose is between 1.5 and 3 grams per day.

— Dr. David Mischoulon, psychiatrist

Massachusetts General Hospital

Can you recommend anything for dysthymia?

Dysthymia is a chronic and tenacious form of depression. One substance we've investigated is N-acetyl cysteine, a substance produced naturally in the body. N-acetyl cysteine supplements are used to reduce mucus in various lung disorders such as cystic fibrosis and to treat acetaminophen (Tylenol) poisoning.

Preliminary studies suggest that it might help improve mood in people with dysthymia — although not in those with major depression. Studies have used supplements containing 1 to 3 grams per day. Just be aware that N-acetyl cysteine supplements often have a strong odor (sometimes like sulfur) that may make them difficult to take.

— Dr. David Mischoulon, psychiatrist

Massachusetts General Hospital

Even the best available medical treatments don't work for everyone. Seeking other sources of relief, roughly four in 10 Americans — and as many as half of those with psychiatric disorders — use herbal supplements and other types of complementary or alternative medicines (CAM) in any given year.

Recognizing how widespread such "alternative" medicines have become, the Massachusetts General Hospital (MGH) Department of Psychiatry convened a one-day conference on the topic. What follows is a quick review of safe — and often effective — natural therapies used for a variety of mental health problems.

For references, please see www.health.harvard.edu/mentalextra.

Folic acid

What it is

Folic acid is a synthetic form of folate, a B vitamin found in green leafy vegetables, citrus fruits, beans, and fortified breads and cereals. It is available as a vitamin supplement or as a prescription medication (leucovorin or L-methylfolate).

What it's for

Depression.

Who may benefit

When combined with an antidepressant, folic acid supplements can boost symptom relief — especially in women.

How much to take

Federal guidelines recommend 400 micrograms (mcg) per day of folic acid for adults. Some research suggests that women of childbearing age should take 800 mcg per day. The dosage of L-methylfolate (Deplin) is usually 15 milligrams (mg) per day when combined with antidepressants.

Words to the wise

Folic acid supplements won't work as a stand-alone treatment for depression. Do not take more than the safe upper limit of 1,000 mcg of folic acid per day.

SAMe

What it is

S-adenosyl-L-methionine (SAMe) is a substance made naturally in the body that boosts production of several neurotransmitters involved in regulation of mood.

What it's for

Depression.

Who may benefit

Used on its own, SAMe works as well as older tricyclic antidepressants. As an add-on treatment, it can boost the effectiveness of a selective serotonin reuptake inhibitor (SSRI) or venlafaxine (Effexor).

How much to take

Adults may benefit from 400 to 1,600 mg per day, although some people will need to take 3,000 mg per day to alleviate symptoms.

Words to the wise

Combining SAMe with an antidepressant is safe, for the most part, but in very rare cases may cause serotonin syndrome — a potentially deadly complication that causes agitation, anxiety, confusion, nausea, vomiting, and palpitations. SAMe can also trigger mania in people with bipolar disorder.

Ginkgo biloba

What it is

This herbal supplement is derived from leaves of the ginkgo tree.

What it's for

Alzheimer's disease and antidepressant-related sexual problems.

Who may benefit

Taken alone, ginkgo biloba is modestly effective at slowing cognitive decline in people with Alzheimer's disease — similar in impact to taking a cholinesterase inhibitor such as donepezil (Aricept), but better tolerated. As an add-on therapy, ginkgo biloba can boost the effectiveness of cholinesterase inhibitors.

Ginkgo biloba may alleviate antidepressant-induced sexual problems.

How much to take

Aim for 120 to 240 mg per day.

Words to the wise

Don't expect fast results. It takes at least eight weeks, and perhaps as much as one year, to notice any cognitive benefit. This supplement does not work as well for people with vascular dementia (the type associated with heart disease). Stressed-out baby boomers and other people without dementia do not get a clear cognitive boost from this supplement.

Valerian

What it is

This herb is derived form the root of a pink flower, Valeriana officinalis.

What it's for

Anxiety and sleep problems.

Who may benefit

Valerian may be an option for elderly people, as it does not cause as many memory and thinking problems as benzodiazepines (sedative medications) do. It may also help children who have problems falling asleep. It may reduce anxiety and improve sleep in children with attention deficit hyperactivity disorder.

How much to take

Adults can take 450 to 600 mg per day. Check with a doctor about dosing for children.

Words to the wise

Valerian often causes headaches and upset stomach. It is not clear whether this herb is safe to use during pregnancy, as it has not been studied for this use. Valerian takes a while to work, so it is not a quick fix for insomnia.

Omega-3 fatty acids

What it is

These naturally occurring fatty acids are most abundant in cold-water fish such as salmon, sardines, and anchovies. People who can't eat fish can also obtain them in fish oil capsules. Look for supplements that contain both EPA and DHA.

What it's for

Bipolar depression and major depression.

Who may benefit

Omega-3 supplements may boost the effectiveness of antidepressants. These supplements may provide a stand-alone treatment option for people concerned about side effects of antidepressants, such as the elderly, people with multiple medical conditions, and women who are pregnant or breast-feeding. In people with bipolar disorder, omega-3 fats may be helpful for treating depression, but can trigger mania, so it's important to take these supplements along with a mood stabilizer.

How much to take

Like the American Heart Association (which recommends omega-3 fats as a good way to protect against heart disease), the American Psychiatric Association recommends that all adults consume fish at least twice a week. Individuals with mood, impulse control, or psychotic disorders should take a daily 1- to 2-gram supplement containing both EPA and DHA.

Words to the wise

Additional supplements may be helpful for people with depression, but don't exceed 3 grams per day, as this increases risk of gastrointestinal bleeding and stomach upset.

St. John's wort

What it is

This herbal supplement is produced from an extract of the plant Hypericum perforatum.

What it's for

Depression.

Who may benefit

Used on its own, St. John's wort may help people with mild or moderate symptoms of depression, but is unlikely to help those with severe symptoms. St. John's wort may also be an alternative to medication for children and adolescents.

How much to take

Adults can take 900 to 1,800 mg in a 24-hour period, ideally by taking two or three capsules over the course of a day.

Words to the wise

St. John's wort can reduce the effectiveness of many drugs, so check with your doctor before using it. Do not take with an antidepressant, as the combination can cause serotonin syndrome — a rare but potentially deadly complication that causes agitation, anxiety, confusion, nausea, vomiting, and palpitations.

Melatonin

What it is

This naturally occurring substance regulates circadian rhythms in the body, such as the sleep/wake cycle.

What it's for

Sleep problems.

Who may benefit

Melatonin improves sleep quality in people with schizophrenia, major depression, and seasonal affective disorder. This supplement may be an alternative to drugs, especially for children and the elderly.

How much to take

Dosages of 0.25 to 0.3 mg per day can improve sleep.

Words to the wise

Begin with low doses, as taking too much can cause daytime sleepiness or confusion. Read product labels, as some preparations contain as much as 5 mg of melatonin per pill.