Depression: Is The Modern Epidemic Real?
It should come as no surprise that physical and emotional health are intertwined and impossible to tease apart. From the perspective of integrative medicine, mind and body are two aspects of an underlying unity. Changes in one always correlate with changes in the other.
Of course, conventional, “biology-explains-all” medicine has long recognized anxiety, depression, and other disturbances of mood as symptoms of physical disease, but it has been slow to accept the possibility that it can work the other way – that imbalances in the mental/emotional realm can cause physical symptoms. Dr. Weil has stated that he is “happy to see that change as new research illuminates the complex interactions of mind and body. The findings also suggest powerful strategies for improving emotional well-being through physical interventions.”
Textbooks Dr. Weil used in medical school included mood disturbances among symptoms of dysfunction in hormone-secreting glands like the thyroid, adrenals, and pituitary. A classic example is the association of depression with hypothyroidism. More than one-third of people suffering from depression are deficient in thyroid hormones; many of them have received long-term treatment with antidepressant drugs before physicians thought to check their thyroid function. That should be assessed in every depressed patient and, if low, corrected.
It is well known that sex hormones affect mood in both men and women. Emotional changes associated with the female menstrual cycle and with menopause are often striking. Depression in some older men can be relieved by boosting low testosterone levels. Presumably, sex hormones have direct effects on the brain and on neurotransmitters involved with our emotions.
More curious is the influence of insulin, the hormone secreted by the pancreas that controls blood sugar (glucose) and the production and distribution of energy in the body. People with diabetes are more likely to be depressed than people without it. Some studies link depression to insulin resistance, the underlying problem in the more common type-2 variety of diabetes, but what is cause and what is effect isn’t known. Insulin receptors occur throughout the brain. Might this hormone directly affect mood? A recent study in animals with type-1 diabetes demonstrated a previously unknown effect of insulin on dopamine signaling in key brain centers. Or is it that the disturbed glucose metabolism of diabetes alters brain function? (Brain cells rely on glucose as their sole source of energy and must have a constant supply of it.) Or do diabetics get depressed just because they have a serious chronic disease that can undermine quality of life? Dr. Weil suspects that it works both ways.
The takeaway message from all of this is to make sure that a physical problem is not responsible for depression – especially an easily treatable one like hypothyroidism. Dr. Weil’s first recommendation for any person who suspects he or she is depressed is to get a complete medical check-up, including necessary blood tests, if one has not been done recently. Resolving an underlying physical problem may be the most valuable course a given person can take to improve his or her emotional set-point.