Bitters, The Gut, And Depression
As with many health problems, depression is frequently the result of processes that involve the gut and its accessory organs (particularly the liver). This is often a particularly important aspect in the elderly because gut function declines with age. It is known that a significant percentage of people over 50 have abnormally low levels of gastric acidity. There is also epidemiological data linking food allergies to depression and anxiety, which could support a common digestive problem causing both. Lack of sufficient saliva, inadequate bile production, and less acidic gastric pH can lead to abnormal bowel flora and poor nutrient absorption. Many elderly (and increasingly large numbers of younger) patients are also maintained on various allopathic medications that significantly and adversely affect salivation and digestion generally (e.g., anti-cholinergics; acid-blockers).
Malabsorption of nutrients is a serious concern and possible cause of depression because numerous nutrient deficiencies, even if marginal, have been linked to depression. Acute depletion of tryptophan (the precursor of serotonin) as well as phenylalanine and tyrosine (the precursors of norepinephrine and dopamine) have been repeatedly shown in experimental studies in humans to depress mood. Rat studies have linked chronic tyrosine deficiency to depressed mood, although rigorous data on the tyrosine-mood connection in humans are not available. Thus, it is quite possible that low-grade protein malnutrition, due either to low intake or poor absorption, may aggravate or precipitate depression. Ensuring optimal nutrition and digestion are critical to avoid and correct this problem.
Low vitamin B12 and folic acid levels contribute to depression, again a particular concern in the elderly where age-related hypochlorhydria can decrease vitamin B12 absorption. One study found that vitamin B12 deficiency doubled the risk of depression in noninstitutionalized women. Vitamin B12 and folic acid are critical intermediates in the methylation process necessary for formation of catecholamine neurotransmitters. These neurotransmitters in general elevate mood. Vitamin B12 and folic acid also maintain normal homocysteine levels. When these two vitamins are deficient, even marginally, homocysteine levels rise and atherosclerosis is promoted. Atherosclerosis can impair blood flow to the brain and promote depression. Therefore, maintaining optimal levels of these two B vitamins is critical. These vitamins may need to be supplemented in some people with depression and many elderly people, but is equally important to also ensure the gut is functioning properly to prevent future deficiency.
Bitter herbs are central to the botanical approach to promoting optimal gastrointestinal function. Historically, an atonic gastrointestinal tract was associated with depression, and bitters were used to stimulate the immune system in patients who were pale, lethargic, or prone to infection. Rudolf Fritz Weiss, MD, stressed that tonic effects of bitters became stronger with prolonged use, and claimed that bitters would neutralize the negative influence of chronic stress on digestion. Numerous modern practitioners also use bitters to stimulate hepatic function and general digestion as a key component to addressing depression in some people.
Table Choosing a Bitter Herb
Patient Features* | Herb | Dose |
Recovering from chronic or acute illness, elderly, cachexic, immunodepressed, strong effect desired | Gentiana lutea (gentian) root** | Tea: 1 tsp (5 g)/cup water simmered 10-15 min, sipped 10-15 min before meals Tincture: 2-4 ml in 2-4 oz water, sipped 10-15 min before meals |
Same as gentian but milder effect desired | Taraxacum officinale (dandelion) leaf | Tea: 1 tsp(5 g)/cup water steeped 10-15 min, sipped 10-15 min before meals Tincture: 2-4 ml in 2-4 oz water, sipped 10-15 min before meals |
Gallbladder problems prominent or chronic gastrointestinal infection present | Artemisia absinthium (wormwood) root | Tea: 1 tsp (5 g)/cup water simmered 10-15 min, sipped 10-15 min before meals Tincture: 0.5-1 ml in 2-4 oz water, sipped 10-15 min before meals |
Liver problems prominent, cholestasis, or chronic gastrointestinal infection present | Berberis aquifolium (Oregon grape) root | Tea: 1 tsp (5 g)/cup water simmered 10-15 min, sipped 10-15 min before meals Tincture: 2-4 ml in 2-4 oz water, sipped 10-15 min before meals |
Liver damage, peptic ulcer, inflammation, otherwise same as for gentian | Swertia chirata (chiretta) root | Tea: 1 tsp (5 g)/cup water simmered 10-15 min, sipped 10-15 min before meals Tincture: 2-4 ml in 2-4 oz water, sipped 10-15 min before meals |
Fever, inflammation, hemorrhagic tendency, cardiovascular problems | Achillea millefolium (yarrow) herb | Tea: 2 tsp (10g)/cup water steeped 10-15 min, sipped 10-15 min before meals Tincture: 3-5 ml in 2-4 oz water, sipped 10-15 min before meals |
Non-tolerance of bitter taste, inflammation, nausea, arthritis | Zingiber officinale (ginger) rhizome | Tea: 1 tsp (5 g)/cup water simmered 10-15 min, sipped 10-15 min before meals Tincture: 1-3 ml in 2-4 oz water, sipped 10-15 min before meals |
Menopausal symptoms, hormonal imbalance | Marrubium vulgare (horehound) herb | Tea: 2 tsp (10g)/cup water steeped 10-15 min, sipped 10-15 min before meals Tincture: 3-5 ml in 2-4 oz water, sipped 10-15 min before meals |
* Other herbs in this table or otherwise may also be appropriate for patients with the features listed.
** Note that there are concerns about the sustainability of this herb in the wild given current trends of use. Use cultivated or ethically wild-crafted herb. Taraxacum officinale (dandelion) leaf is a highly sustainable and reasonably similar substitute.
Bitters are substances capable of stimulating digestive powers and appetite in cachexic, debilitated, and healthy people alike. The quinoline alkaloids of Cinchona spp. (Peruvian bark), monoterpene secoiridoid glycosides of Gentiana spp. (gentian), and the sesquiterpene lactone dimers of Artemisia absinthium (wormwood) are some of the most bitter substances known, and these herbs are among the most frequently used bitters. Early studies established that
bitters worked by taste, and did not appear to affect digestive function in healthy animals. Human studies have demonstrated that gentian and wormwood can increase salivation as well as gastric and bile secretion when taken five minutes before meals. Though bitters can stimulate digestion without being tasted, their effects are probably optimized by allowing the bitter taste to stimulate the cephalic as well as intestinal phases of digestion. Direct connections between bitters and the mind have not been studied. To choose a bitter, refer to Table Choosing a Bitter Herb.