We are told that depression is caused by a chemical imbalance in the brain, especially among the chemicals that allow nerves to communicate with each other, called neurotransmitters.

One of the most important in relation to depression is serotonin. Many factors influence brain function and serotonin levels. Genetics is one, although for most people it is not the most important. The greatest trigger for depression is lifestyle, especially diet. Our modern diets are very different from those of our ancestors. We eat a lot of processed grains, especially sugars; “vegetable oils,” which have an unbalanced fatty acid profile; and perhaps the worst culprit of them all, modern highly hybridized wheat. All these dietary stresses — blood sugar spikes, fatty acid imbalance and gluten — create inflammation throughout our bodies, including the brain. One study of 9,000 people showed that a diet with a lot of “junk food” was associated with a 50 percent greater chance of developing depression, with those who eat the most showing the highest risk.

For a few of my patients with depression, simply avoiding wheat and other sources of gluten has resolved their problems.

Of course, the drug companies would have you believe the only real treatment for depression is medication. This is not entirely correct, on two fronts. First, studies have not shown medications to be very effective for most depression sufferers. One large meta analysis (a review of a number of previous studies) showed that medications are only effective for those with the most severe depression; those with mild or moderate depression symptoms did just as well with a placebo.

This is consistent with my experience. A small percentage of patients are greatly helped by the medications, but most are not.

Which brings me to my second point: There are natural, drug-free treatments for depression that work well for many patients. It makes sense to me that patients with less severe depression are perfect candidates for wellness care (although even those with more severe symptoms can be helped). Obviously an important step is to improve lifestyle, but that may be difficult in the beginning. In our office, treatment is focused on relieving the symptoms first. Once there is some relief, then it is easier for the patient to change their lifestyle.

There are treatments that help depression directly. I have had the best results with a combination of acupuncture and supplements designed to normalize brain chemistry naturally. If a patient is on medications for depression, we use only food-based supplements, as there may be reactions with herbals.

However, for many depressed patients, underlying health problems need to be addressed. Digestive problems are common, and almost typical with depressed patients — 90 percent of the body’s serotonin is made in the gut. Improving digestive function with acupuncture, supplements or other natural treatments is helpful. Of course, chronic pain (and the resulting interrupted sleep, inactivity and medication use) can be a big cause. Often this responds to manipulation, and can be combined with acupuncture and natural anti-inflammatory supplements.

Another important cause of depression is medication use. Many drugs have depression as a side effect, including Accutane (for acne); medications for high blood pressure; estrogen preparations, such as birth control and menopausal medications; Tamiflu; Chantix, used to help quit smoking; statins, including Lipitor and Crestor; and even anti-inflammatory drugs like ibuprofen (sold as Motrin and Advil), aspirin and naproxen. Ironically, worsening depression or anxiety is listed as a side effect of many medications used to treat depression, especially in the beginning of care.

For some of these medications, depression is listed as a rare side effect. But side effects become more likely with the more drugs a person is taking. This is especially true of “polypharmacy,” or taking four or more medications. A Swedish study showed that from 1992 to 2002, the percentage of elderly people on four or more medications jumped from 18 percent to 42 percent.

The likelihood of an important drug reaction, including not only depression, but also overall sluggishness and lethargy, is quite high with polypharmacy. Many of these patients can get off some of their medications with wellness care. One study showed an 85 percent reduction in prescription drug use among patients who chose doctors of chiropractic as their family doctors.

Some medications can be stopped without withdrawal symptoms. For example, it is safe for a patient to stop taking anti-inflammatory medications. Other medications need to be “titrated,” meaning it is best to gradually reduce the dose. This is especially true of most of the medications for depression. Suddenly stopping the drug can have serious side effects.

Like most chronic problems, depression is best treated with a combination of lifestyle improvements and wellness-based treatments. Medications should be a last resort. For some, they give tremendous benefits, but for most patients there are alternatives that are very effective, with far fewer side effects.

Dr. Michael Noonan practices chiropractic, chiropractic acupuncture and other wellness therapies in Old Town. He can be reached at noonanchiropractic@gmail.com.