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*HerbDose
Recovering from chronic or acute illness, elderly, cachexic, immunodepressed, strong effect desiredGentiana 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 desiredTaraxacum officinale (dandelion) leafTea: 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 presentArtemisia absinthium (wormwood) rootTea: 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 presentBerberis aquifolium (Oregon grape) rootTea: 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 gentianSwertia chirata (chiretta) rootTea: 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 problemsAchillea millefolium (yarrow) herbTea: 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, arthritisZingiber officinale (ginger) rhizomeTea: 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 imbalanceMarrubium vulgare (horehound) herbTea: 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.