Nutritional Approaches to Mental Health

Let food be thy medicine.– Hippocrates

Besides the oxygen we breathe, all that we need to survive comes from what we eat. Food nourishes both the body and the brain. In fact, the brain has first call on the available supply of nutrients. Therefore, the first effects of nutritional deficiencies are often mental symptoms.

When orthomolecular psychiatrists refer to a nutritional deficiency, they are not necessarily talking about the prevention of a traditional deficiency disease, such as beriberi, a once-common illness that is fortunately now rare due to vitamin B1 food supplementation. However, lesser subclinical deficiencies are quite common. While not enough to bring on overt physical symptoms, they are often sufficient to stimulate changes in brain chemistry, and affect mood. Antidepressants, including St. John’s wort, are not likely to be successful in treating these cases until the specific deficiency is corrected.

In this chapter, I will introduce you to someone who was helped by nutritional therapy, and present information on vital depression-fighting nutrients. I’ll then discuss other possible causes of depression-including illnesses that St. John’s wort can help alleviate.

Treating the Entire Person

When treating depression, it is important to address all of a patient’s problems, both biochemical and psychological, if healing is to take place. Jeff is a good example.

Jeff, a 19-year-old college freshman with no prior history of emotional problems, was brought to see me by his concerned father. “I don’t know what to think. Jeff has been withdrawing more and more lately, won’t join us at the dinner table, hasn’t been finishing his assignments, and says there’s nothing wrong.” Further questioning revealed that Jeff had been popular in high school, a good student, and a member of the basketball team. Yet he was now failing at the local college he was attending, and according to his father, was “not his old self.”

As his father talked, the tall, somewhat thin, young man sat across from me, looking sullen. I asked his father to leave the room so I could see Jeff alone. There was little change in his demeanor. A series of questions went through my mind: Was he depressed? Was he psychotic, hearing voices that he would not admit to? Or, putting on my orthomolecular hat, was he eating a typical teenage diet of fast food and soft drinks, which could leave him deficient in nutrients needed for adequate brain function?

I determined from his rather brief answers that he was not in any immediate danger, but that he would need more time before he trusted me enough to talk more freely. Given his good prior history, I was willing to wait another week or so before doing anything more definitive, such as prescribing medication. My philosophy is “natural is preferable,” since it addresses the root of the problem, and not the symptoms. Also, young people often feel stigmatized by a psychiatric diagnosis, especially when it is accompanied by a prescription.

Jeff agreed to take some daily vitamins, minerals, and herbs. When he came alone to see me two weeks later, he was far more communicative, and appeared to have gained some weight. He had indeed been going through a difficult time, with inner conflict about life issues that he had not had to deal with in high school. He was also feeling that he had let down his parents in some way by not being as competent, decisive, and independent as he expected himself to be. This confusion and depression is not unusual for first-year college students, who face a radical change from familiar high school surroundings. However, he admitted that he had been helped by my advice despite himself. While he had “resented my Dad’s dragging me to some shrink,” he had followed my instructions by taking the vitamins and herbs three times daily with meals. This instruction also assured that he would eat regularly, and likely, with the family. He said that the supplements seemed to calm his worried mind, and gave him energy and clarity at the same time. He turned out to be quite bright and articulate, in contrast to our initial contact.

What were these pills? The basic multivitamin/multimineral capsules are standard fare in my office, often restoring energy and emotional balance in depleted individuals. The herbs were St. John’s wort, the herbal antidepressant, and kava-kava, a South Pacific herb used to help relieve stress. As his depression and anxiety lifted, Jeff was able to think more clearly, and began to seek my advice. Psychotherapy, or any learning, can take place much better when the brain is working properly. Any prior attempts at therapy with Jeff would probably have driven him further away. However, with the proper brain food, he was able to have some insight into his situation, and move in the direction of healing.

Jeff’s moodiness might have been ignored by those around him, as friends and family of depressed people often rationalize that while something is not quite right, the person remains healthy in most respects. But sweeping these difficult issues under the carpet may lead to catastrophic consequences. Fortunately for Jeff, early intervention on several levels prevented his disturbance from becoming chronic.

Nutritional Balance and Depression: Amino Acids, Vitamins, Minerals, and Other Nutrients

Like Jeff’s diet, the standard American diet is deficient in many of the nutrients we need to stay healthy, both physically and mentally.

What causes these deficiencies? We need only consider the high-sugar, low-fiber, additive-preserved foods that many people consume on a regular basis, combined with the impaired absorption of nutrients that accompanies such poor nutrition. Many people simply do not get the important nutrients needed for good health. They are at once overfed and undernourished, and a poorly nourished body contains a malnourished brain.

In my own practice, I prefer to begin psychotherapy only after excluding an underlying physical cause. In fact, deficiencies in almost any of the vitamins and minerals can show up first as emotional or mental symptoms, such as depression, anxiety, or impaired memory and concentration. Because lab tests to determine specific deficiencies can be costly, I most often recommend the use of multivitamin/multimineral supplements. (For more information on vitamins and minerals, see Prescription for Nutritional Healing by James and Phyllis Balch(Avery) and The Real Vitamin and Mineral Book by Shari Lieberman and Nancy Bruning (Avery)).

Let’s look at the amino acids, vitamins, minerals, and other nutrients that are especially important for mental health. (The essential fatty acids are also significant in the prevention and treatment of depression and other disorders.)

Amino Acids

Depression can result if brain messengers called neurotransmitters are in short supply. Synthetic antidepressants work by raising neurotransmitter levels in the brain, and it is likely that St. John’s wort does the same thing. Amino acids, the building blocks of protein, are the precursors, or raw materials, for neurotransmitters and other mood-regulating compounds. It is possible to reverse depression by loading up on these amino-acid precursors.

There are three amino acids that are most directly related to mood and depression: phenylalanine, tyro-sine, and tryptophan. Phenylalanine and tyrosine produce the neurotransmitter norepinephrine, and tryptophan is eventually converted to serotonin.

Research has proven the effectiveness of amino acid therapy in fighting depression. Both phenylalanine and tyrosine-which is created in the body from phenylalanine-have been found to be as effective as the antidepressant drug imipramine. Phenylalanine has also been shown to reduce pain by preserving brain levels of endorphins, the body’s natural painkiller. Tyrosine is helpful in the treatment of PMS and chronic fatigue syndrome. Tryptophan, which the body converts into the precursor 5-hydroxytryptophan (5-HT), has also been found to be as effective as the synthetic antidepressants.

Since amino acids are found in such high-protein foods as meat, fish, and eggs, you might think that the way to increase your amino-acid levels would be to eat more of these foods. However, disorders such as depression are caused by specific amino-acid imbalances. I recommend that you work with your physician to determine which amino acids you are deficient in before undertaking a supplementation program (see The Way Up From Down by Pricilla Slage (Random House)). If you are already taking antidepressant medication, you can keep taking it while your biochemistry is being brought into balance, and then discontinue the medication after the amino acid therapy takes effect. Amino acids can be combined with St. John’s wort. It is important to take sufficient a-mounts of the amino-acid cofactors, such as vitamin B6, which your body needs to properly process amino acids. Tryptophan is available only by prescription at compounding pharmacies or pharmacies that carry natural medicines, but 5-HT is now available from a limited number of suppliers. I still recommend that amino acid therapy be carried out under professional supervision, to insure correct product and dosage.


Our bodies cannot create vitamins, so a well-balanced, supplemented diet is necessary to obtain adequate amounts of these essential nutrients. Vitamins act as catalytic agents in the body, helping to speed up the chemical processes that are vital for both survival and brain function. As a result, vitamin deficiencies can sometimes manifest themselves as depression. Fortunately, when these deficiencies are treated with supplements, there is a reversal in symptoms.

The Recommended Daily Allowance (RDA) is inadequate. These figures are based on the minimal requirements for prevention of severe deficiency disease, rather than on the requirements for optimum health or deficiency correction. My recommendations exceed the RDA. For vitamins B1, B3, and B6, I recommend a daily dose of 50 milligrams (mg), with higher doses for specific disorders.

Important vitamins for mental health include:

  • Vitamin B1 (thiamine). The brain uses this vitamin to help convert glucose, or blood sugar, into fuel, and without it the brain rapidly runs out of energy. This can lead to fatigue, depression, irritability, anxiety, and even thoughts of suicide. Deficiencies can also cause memory problems, loss of appetite, insomnia, and gastrointestinal disorders. The consumption of refined carbohydrates, such as simple sugars, drains the body’s B1 supply.

  • Vitamin B3 (niacin). Pellagra-which produces psychosis and dementia, among other symptoms-was eventually found to be caused by niacin deficiency. Many commercial food products now contain niacin, and pellagra has virtually disappeared. However, subclinical deficiencies of vitamin B3 can produce agitation and anxiety, as well as mental and physical slowness. Mega-doses of the vitamin have been found to reduce these symptoms.

  • Vitamin B6 (pyridoxine). This nutrient is essential for the creation of neurotransmitters. Studies have found a strong correlation between vitamin B6 deficiency and depression. Shortages can also produce anemia, numbness, tingling in the limbs, and convulsions. Vitamin B6 has been shown to help women with premenstrual syndrome (PMS). Malabsorption diseases and certain drugs, including MAOI antidepressants (see Prozac and Beyond-The Synthetic Antidepressants) and birth control pills, can cause deficiencies. I recommend that all women on birth control pills take 50 mg of vitamin B6 daily.

  • Vitamin B12 (cobalamin). Because vitamin B12 is important to red blood cell formation, deficiency leads to an oxygen-transport problem known as pernicious anemia. This disorder can cause mood swings, paranoia, irritability, confusion, dementia, hallucinations, or mania, eventually followed by appetite loss, dizziness, weakness, shortage of breath, heart palpitations, diarrhea, and tingling sensations in the extremities. Deficiencies take a long time to develop, since the body stores a three- to five-year supply in the liver. When shortages do occur, they are often due to a lack of intrinsic factor, an enzyme that allows vitamin B12 to be absorbed in the intestinal tract. Since intrinsic factor diminishes with age, older people are more prone to B12 deficiencies. Thus, this vitamin is often given as an injection, or as tablets that dissolve under the tongue, to bypass the digestive tract. Vitamin B12 can benefit the 10 to 30 percent of depressed individuals who are deficient. The dose is 1,000 micrograms (mcg).

  • Folic acid (folate). Folic acid, another B vitamin, helps assist in the creation of many neurotransmitters. It is also essential to the production of hemoglobin, the oxygen-bearing substance in red blood cells, so deficiencies often lead to anemia. Studies have shown abnormally low levels of this vitamin in from a quarter to a third of all depressed persons. Other symptoms include fatigue, lower-extremity problems, and dementia. Orthomolecular psychiatrists have used folic acid supplements for many years to reduce the frequency of relapses in their patients. Poor dietary habits contribute to folic acid deficiencies, as do illness, alcoholism, and various drugs, including aspirin, birth control pills, barbiturates, and anticonvulsants. It is usually administered along with vitamin B12, since a B12 deficiency can mask a folic acid deficiency. The usual dose is 800 mcg. Higher doses, though safe, require a prescription.

  • Vitamin C (ascorbic acid). Vitamin C, widely known for its antioxidant abilities, is also important for mental health. Subclinical deficiencies can produce depression, which requires the use of supplements. One study showed that a single 3-gram dose of vitamin C reduced symptoms by 40 percent in eleven manic and twelve depressed patients after only four hours. Supplementation is particularly important if you have had surgery or an inflammatory disease. Stress, pregnancy, and lactation also increase the body’s need for vitamin C, while aspirin, tetracycline, and birth control pills can deplete the body’s supply. A good maintenance dose is 1 to 3 grams daily, with more for depressed people, smokers, and those exposed to toxins of various kinds.


There are at least fifteen minerals that are essential to health. Either inadequate or excessive dietary intake can lead to mental and behavioral problems, including depression, often before any physical symptoms appear.

Minerals important to mental health include:

  • Sodium and potassium. These minerals are considered together because they determine the body’s electrolyte balance, which regulates water levels. Eating a lot of salty food (sodium) disrupts this balance. This not only produces high blood pressure, but also affects neurotransmitter levels, producing depression and PMS. In addition, the misuse of diuretics, or “water pills,” can lead to potassium deficiency, which in turn can manifest itself as depression. A good daily dose is from 200 to 400 mg.

  • Iron. Iron deficiency can result in anemia, which can produce symptoms such as depression, irritability, fatigue, loss of attention span, and insomnia. One study found that nearly half of all premenopausal women and a third of all children do not get enough iron, so supplementation in these groups could have a significant impact on the frequency of depression and other disorders. From 15 to 30 mg a day is a good maintenance dose. On the other hand, excessive iron can lead to toxicity, especially in men, who are not losing the mineral regularly through menstruation. Therefore, men shouldn’t supplement with iron unless under a doctor’s direction.

  • Magnesium. This mineral assists in all of the body’s energy reactions.

Deficiency can result in depressive symptoms, along with confusion, agitation, anxiety, and hallucinations, as well as a variety of physical problems. Most diets do not include enough magnesium, and stress also contributes to magnesium depletion. Other possible reasons for a deficiency include kidney or parathyroid disease, high blood pressure, chronic fluid loss, alcoholism, and malabsorption disorders. Several studies have shown that magnesium injections can bring relief from symptoms such as fatigue, aches and pains, weakness, and lethargy. I frequently give magnesium shots for migraine headaches, PMS, and allergies. A daily maintenance dose is 400 to 800 mg, with more needed to correct deficiencies.

  • Calcium. Depressed individuals often have excessive calcium levels, particularly those with bipolar disorder (see Chapter 2). When these patients recover, their calcium levels usually return to normal. Depression can also occur in cases of calcium deficiency, long before the appearance of physical deficiency symptoms. In addition, calcium works with magnesium to maintain balance, or homeostasis, in the body, much as sodium and potassium work together to achieve balance in water levels. If you are supplementing with calcium, you will need to take one-half as much magnesium, sometimes even more, to keep the two properly balanced. This includes women who are taking calcium supplements to prevent osteoporosis. A good daily dose is 800 to 1,000 mg.

  • Zinc. Zinc deficiencies frequently lead to depression, since this mineral is essential to many processes related to brain function. In addition to irritability, mental slowness, and emotional disorders, zinc deficiency can produce changes in taste and smell sensations, a loss of appetite, reduced immune function, and rough skin. These symptoms are particularly common among older people and in women, especially those with eating disorders. An excellent treatment for anorexia and bulimia uses high doses of zinc, beyond the recommended 15 to 30 mg daily.

Other Nutrients

There are two other nutrients that are important to mental health. S-adenosylmethionine (SAM), a natural, active form of the amino acid methionine, helps process a wide variety of neurotransmitters, including norepinephrine, dopamine, phosphatidylcholine, serotonin, and melatonin. In Europe, SAM is sold as an antidepressant, where it performs as well or better than synthetic drugs without the side effects.

Phosphatidylserine, another substance that is particularly plentiful in the brain, helps to ensure proper nerve function by keeping the membrane surrounding each brain cell fluid and flexible. Proper membrane fluidity affects nerve signal transmission, the binding of neurotransmitters to receptor sites, and the activity of monoamine oxidase, or MAO. Phosphatidylserine can also enhance mood, behavior, and mental function by increasing the accumulation, storage, and release of several neurotransmitters. I have used it successfully in my practice as an adjunct in treating depression and to improve cognitive functions such as thinking and memory, in doses of 100 mg two to three times a day. It should not be combined with an antidepressant without a doctor’s supervision, nor is it recommended for bipolar disorder.

Other Possible Causes of Depression

There are several illnesses that can mimic depression, including chronic fatigue syndrome, systemic candidiasis, and hypoglycemia, or low blood sugar. St. John’s wort can be especially useful in treating the first two disorders; both are related to immune dysfunction, and St. John’s wort can fight depression and strengthen the immune system (see St. John’s Wort – The Versatile Herb). Two additional factors to consider in depression are hormonal imbalances and the effects of pollution. (See Solving the Puzzle of Chronic Fatigue Syndrome by Michael Rosenbaum, M.D. and Murray Susser, M.D.)

Chronic Fatigue Syndrome

Chronic fatigue syndrome (CFS) is an often-baffling disorder that can thoroughly disrupt someone’s life, as Melissa discovered.

Melissa, a successful 38-year-old professional, described herself in desperate terms: “I feel like I’m losing my mind. I’m absent-minded, simple tasks overwhelm me, and I’m in tears at the drop of a hat. I’m exhausted most of the time. I can barely get up in the morning. All day, there’s a constant struggle to stay awake. I feel my life is over!”

Melissa’s medical history revealed unaddressed explanations for her desperation. Six months earlier, she’d had the flu. Despite her apparent recovery after about a month, she never fully regained her former strength and energy. She could no longer exercise as before, and found that it depleted rather than energized her. She drank coffee to boost her energy, but after a while even that did not work.

I ordered several blood tests. They revealed a number of problems, any one of which could cause fatigue, anxiety, and depression: iron-deficiency anemia, elevated Epstein-Barr viral antibodies-which indicated both a past and presently active viral infection-and hypoglycemia. I prescribed an iron supplement for the anemia, a standard medical diagnosis that is often overlooked. However, in contrast to standard treatment, I also prescribed immune-boosting and energizing herbs, including astragalus, echinacea, goldenseal, licorice, and Siberian ginseng. In addition, Melissa took St. John’s wort, mega-doses of vitamins and minerals, and specific amino acids, especially lysine and cysteine, for viral defense. Within three months she was feeling like herself again-active, enthusiastic, optimistic, and no longer depressed.

Melissa’s flu turned out to be Epstein-Barr virus, a chronic, relapsing form of infectious mononucleosis that is part of CFS. CFS appears to be caused by any one of a group of viruses that can lie dormant for months or years at a time, then be reactivated by physical or emotional stress. Symptoms include depression, extreme fatigue, nonrestorative sleep, impaired memory and concentration, anxiety attacks, intermittent low-grade fevers, sore throat, swollen lymph glands, muscle aches and pains, and allergies. One feature that distinguishes CFS from depression or other causes of fatigue is a negative response to exercise. While most individuals feel energized after exercise, chronic fatigue patients feel worse.

Systemic Candidiasis (Candida Infection)

Systemic candidiasis is caused by the fungus Candida albicans, an organism normally found in the intestines and elsewhere that can grow out of control under certain conditions. Joni is a good example of how candidiasis can affect mood.

Joni, an overweight, depressed, 32-year-old secretary, was in tears. “Everything I eat makes my stomach bloat like I’m six months’ pregnant. I keep dieting, and I can’t lose weight. My brain is like mush: I’m absent-minded, and afraid I’m going to lose my job. Yesterday, I went to get coffee for my boss, went to the file drawer instead, and couldn’t remember what I was doing!” She craved sugar and bread, and had repeated vaginal yeast infections and severe PMS. She scored high on a candida questionnaire, and a candida antibody blood test confirmed the diagnosis.

Joni had taken antibiotics as a teenager to combat acne. This set her up for overgrowth of yeast in the intestinal tract. She had also started taking birth control pills at the age of twenty-four, leading to a hormonal state that favors candida growth. Fortunately, she responded well to treatment, which included a healthy diet, two acidophilus capsules a half hour before each meal, and two tannic acid capsules taken three times daily. Her abdominal bloating cleared, as did her PMS, mood swings, and mental fogginess. She was finally able to lose weight, as well.

Systemic candidiasis, also known as chronic Candida albicans or candida hypersensitivity syndrome, is similar to CFS in its effects. Candida albicans is normally kept in balance within the gastrointestinal tract by the friendly bacteria that aid in digestion, such as acidophilus. If these friendly bacteria are weakened, candida can start to overgrow, causing a multitude of symptoms that are often erroneously labeled psychosomatic.

As in Joni’s case, long-term use of antibiotics kills the body’s friendly bacteria, making it easier for candida to overgrow. When used with steroids, antibiotics also suppress the immune system. Repeated pregnancies and prolonged use of either birth control pills or progesterone can change the body’s hormonal balance, which can also lead to candidiasis. A diet high in sugar will promote candida growth, both because the yeast grows on sugar and because sugar has an immune-suppressant effect.

Like CFS, candidiasis is a controversial diagnosis in orthodox medical circles, usually acknowledged only in severely debilitated patients. For more information on this subject, see The Yeast Connection by William Crook, M.D. and The Yeast Syndrome by John Parks Trowbridge, M.D.


Melissa, the patient with CFS, also had hypoglycemia. This disorder is often related both to stress and to poor eating habits, both of which affect the adrenal glands. As we saw in Chapter 3, our adrenal glands produce hormones that allow us to deal with emergencies. One of these hormones, cortisol, raises blood-sugar levels temporarily. After a while, though, blood-sugar levels plummet. When this cycle repeats itself enough, the overtaxed adrenal glands are exhausted-and so are we.

Hypoglycemia can present itself in a variety of ways: depression, irritability, anxiety, panic attacks, fatigue, “brain fog,” headaches (including migraines), insomnia, muscular weakness, and tremors, all of which may be relieved by food. There can be cravings for sweets, coffee, alcohol, or drugs; in fact, many addictions are related to hypoglycemia. In Melissa’s case, in addition to the CFS therapy, I prescribed a diet in which sugar, white flour, coffee, and alcohol were to be eliminated, and replaced by small, frequent meals containing complex carbohydrates, high fiber, and protein.

Hormonal Imbalances and Pollution Effects

Imbalances in either sex or thyroid hormones can cause depression. Sex hormone imbalances are more common in women because of the complications presented by the menstrual cycle, as we can see in Lonnie’s case.

Lonnie, a 40-year-old secretary, was still depressed, anxious, irritable, and tired despite six months of weekly therapy sessions, after which her therapist had referred her to me. Lonnie was dissatisfied with her job, her family, and life in general, and had severe PMS. Blood tests showed that she was premenopausal, that time period prior to menopause when hormone levels are already beginning to change. I prescribed the female herbal remedies dong quai, vitex, and black cohosh. I also had her take two hormones, natural progesterone and dehydroepiandrosterone (DHEA), plus vitamin B6, magnesium, and evening primrose oil. Considering her level of depression and anxiety, I added St. John’s wort and kava, both noted for their effects on PMS and menopausal symptoms. After about six weeks on this regimen, not only did her PMS go away, but so did her depression and irritability. Her energy level and sexual response both improved. We see how in Lonnie’s case, addressing the physical problem had a positive effect on her emotions.

Natural hormone therapy is far more preferable than the usual synthetic hormone replacement therapy. Unlike the synthetic hormones, natural progesterone and estrogen have few side effects, and are available at compounding pharmacies.

Low levels of thyroid hormone, produced by the energy-generating gland located below the Adam’s apple, can also cause depression, as in Randi’s case.

When Randi, a 34-year-old guidance counselor, came to see me, she was depressed, tired, unable to get up in the morning, and feeling overwhelmed by her job. She was often cold, especially her hands and feet. She also had thinning hair, dry skin, and constipation. When I asked about thyroid disease, she said that it had been suspected before, but her tests had been normal. an underactive thyroid, however, can often hide behind “normal” blood tests. Although Randi’s thyroid hormone levels were normal, she did, in fact, have hypothyroidism, or low thyroid function. I prescribed thyroid hormone from natural sources and asked her to monitor her body temperature so I could adjust her dosage. She asked whether this would suppress her own thyroid function and whether she would need supplementation for life. The answer was “no” to both questions. The treatment actually supported her own thyroid gland, allowing it to heal. Within ten days of starting the program, Randi’s mood and energy lifted, and she was feeling alive again.

Dr. Broda Barnes has developed a technique of monitoring thyroid function through body temperature that is used by many alternative health practitioners. If the temperature is consistently low, the patient is treated with thyroid replacement therapy, and progress is monitored both by clinical signs and symptoms, and by a rise in temperature.

Depression can be caused by a wide variety of pollutants, especially the heavy metals: lead, mercury, arsenic, and bismuth. Aluminum, though technically not a heavy metal, is also toxic. Other pollutants can cause problems, too. Carbon monoxide reduces the brain’s oxygen supply, which causes a variety of psychiatric and neurological symptoms, including psychotic depression. Insecticide exposure can result in depression, confusion, drowsiness, and decreased concentration. Other volatile substances, such as paint and solvents, can also result in depression and other psychiatric symptoms when the fumes are inhaled for prolonged periods of time. The best way to avoid exposure to pollutants is to minimize your risks.

The psychiatrist can be not only a healer, but an educator and facilitator as well, helping people to make wise choices in lifestyle, diet, supplements, and medications. Rather than curing depression, the goal is balance, in body as well as in mind and spirit. Imbalance in one area is reflected in problems in other areas, and the weakest link shows first. Ideal treatment is holistic: Evaluate the whole person and treat each imbalance accordingly. Address as many areas-physical, emotional, and spiritual-as possible, thereby encouraging shifts that move the individual toward balance and health.

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Written by Hyla Cass MD

Explore Wellness in 2021