Theory
Below are the results of my researches on theory. Like most of these note pages, it is a work in progress. Categories will move to their own pages as they get too large for this overview page.
More so than almost any other topic it is paramount here to remember where I draw information from. Assertions below will be ennobled with an asterisk that links to the source. In some cases, this source will be a physical book which is represented by a reference page.
| Saturated Fats | Meats, eggs, whole-fat dairy |
| Mono-unsaturated Fats | Olive and canola oil |
| Poly-unsaturated Fats | Seeds, nuts, fish, vegetable oils |
| Trans Fats | Fried foods and some commercially baked goods |
Ah, the much lauded and little understood world of protein. How much does one need a day?
Evidently the gut's microbiome has wide-ranging effects on the body. For example, 90% of the body's serotonin resides in the gut and is manufactured there by bacteria (as well as in other places). GABA (make ref. when reading ch 2), norepinephrine, dopamine, tryptophan, and other import substances are also produced there. Proper microbiome composure is needed for the function of all these important regulatory chemicals. So it's rather important to keep that biome safe and functional.
An unbalanced microbiome is called dysbiosis. Irregular eating times, high-fat diets, and especially antibiotics can bring this failure about.
Unfortunately it seems the minutia of the interoperability between brain and gut is one of those places where scientists wave their hands and say "it's complex and poorly understood". However, empiricism has taught us that use of probiotics can have vast impacts on cognition, emotion, and behavior. Trials with specific probiotics have cured depression and anxiety, reduced stress, and mitigated attention deficit issues.
The bad news is that the FDA does not regulate the probiotic market, so it's nearly impossible even for experts to determine which products work. It's tentatively shown that probiotics work best when actually present in food (think yogurt) rather than in supplements or capsules. However, getting probiotics to actually work is pretty tricky and most products (even the food ones) are snake oil. Most alarmingly, a probiotic formulation called VSL#3 was tested and proved to function. However, it was sold as a brand to another company that then changed the production method rendering it inert. Only later did a lawsuit bring the change to light.
Levitin hesitatingly recommends two actual products, and he buries them in the notes at the back of the book. Both are supplements anyways.
Prebiotics merit further research. They are used to provided food to any probiotics taken.
Free radicals are real, and are bad. The oxidative stress they produce assists the development of a range of bad things (cancer, diabetes, neurological disorders like Parkinson's and Alzheimer's).
Unfortunately, antioxidant supplements probably don't work and there's not much evidence to confirm that even dietary antioxidants (e.g. blueberries) help either*. It is likely that antioxidants follow a step function*. The most certain route, it appears, is to avoid producing antioxidants to begin with. Sources include*:
Levitin suggests just one food to help with relieving oxidative stress - true virgin olive oil*.
Cholesterol circulates in the blood and performs important functions. Low-density lipoprotein (LDL) is the "bad" cholesterol and high-density lipoprotein (HDL) is the "good" one. LDL is "bad" because it has a tendency to build up on the walls of arteries and cause the pumps to work harder. More LDL is produced as people age and a part of the ratio of production is determined by genetics. Curiously, there's not a scientific consensus that the cholesterol in food actually contributes to your body's cholesterol levels*.
Fortunately, there are some known nutritional methods to mitigate LDL. Dietary methods are listed below*:
Upshot: acceptable levels of soluble fiber and Omega-3 should be maintained. Avoid trans fats.
This form of fat has been widely celebrated by media in my lifetime. However, it seems that the true evidence in favor of this substance is somewhat less warm. Rather than providing tremendous health benefit with consumption, it seems Omega-3's are instead tremendously risky to completely omit. Rather, consumption of Omega-3's are something like a step function and once the minimum needed amount is reached no further superpowers are granted to us.*
That being said, consumption of fatty, Omega-3 containing fish presents the body with advantageous matrix effects whereby the orchestra of "fats, vitamins, minerals and supporting molecules"*. Foods that contain Omega-3 naturally are highly desirable. It's only Omega-3 supplements that are likely useless.
Omega-3 fats are essential for continued production of myelin, without which the brain can not shield neuron signals.
This is so curious, but it seems that simply being hungry stimulates the brain. As far back as childhood I suspected that hunger was a motivational tool, but I figured that the reason was due to a promise of future reward. However, Levitin notes that caloric restriction actually induces production of substances that improve the brain's function. I've written more on this topic here.
A study of many modern hunter-gatherer societies finds that diets vary substantially, yet those societies all shared excellent health*. It follows that there's no one subset of traditional food (e.g. "Mediterranean") that is ideal.