Mood changes are affected by imbalances in the neurotransmitters serotonin (thought to primarily influence mood) and dopamine, noradrenaline, and adrenaline (thought to primarily influence motivation). Betaine (from choline) and SAMe (S-adenosylmethionine) help make these neurotransmitters. Choline, folate, B-12, and methionine (from protein) are interrelated & deficiencies of one can result in an increased need for others. Elevated blood levels of homocysteine, often associated with elevated risk of heart disease and stroke, are frequently seen when any of these nutrient levels are low.
The most concentrated food source of choline is egg yolks, yet many are concerned about eating eggs because they are also a rich source of dietary cholesterol. But the majority of people (70-75% of the population) experience only mild or no alterations in plasma cholesterol concentrations when challenged with high amounts of dietary cholesterol. In the other 25-30%, egg intake is associated with increases in both LDL- and HDL-cholesterol and the LDL is of the large particle-size (associated with lower risk than the small particle-size LDL-cholesterol).
In addition to being an excellent source of choline, eggs are an inexpensive source of high-quality protein and egg yolks are also a good source of protective antioxidant carotenoids (especially lutein). Much of the research linking egg consumption to heart disease risk did not control for other important dietary factors likely to have increased risk, including the amount of saturated and trans fats, oxidized cholesterol (from breakfast meats and cheeses), and refined carbohydrates (especially sugar) often associated with egg consumption. Here’s an excellent recipe using Eggs: Eggs Poached Over Greens (Light Meal for One)
I really loved this quote from the wonderful review article by Pizzorno on homocysteine in the August 2014 issue of Integrative Medicine: “… it is important that we refrain from the current habit of so many clinicians and patients of defining any molecules in the body as bad. Although there are certainly a few that appear toxic at any level, such as lead, there are others, even arsenic, that at some level are beneficial. The problem is not the molecule, but what happens when the molecule is damaged –such as oxidized cholesterol—or at such a high level in the body –such as blood sugar higher than 200—that it alters physiology. These are typically not the result of ingestion of the molecule, but rather all the physiology around them that is dysfunctional.”
So we come again to the conclusion that “health is a question of balance,” and whole, fresh, minimally processed foods are still our best choices.