“One cannot think well, love well, sleep well, if one has not dined well.” —Virginia Woolf
Last week, we discussed the wonderful work of Felice Jacka, who fought the conservative establishment of psychiatry to show that food can improve our mood and our cognition. Here we find out what the mechanism is and then expose the six food groups that Jacka found were most useful
.
Why Does This Happen?
In 2004, Nobuyuki Sudo at Kyushu University found that germ-free mice behaved differently than their normal germy cousins, but when they were fed a probiotic diet, they recovered normal behavior. Here was a weird connection between gut microbes and brain behavior and development. It offered an early peek into the gut-brain axis.
At least part of nutritional psychiatry is involved with the trillions of microbes in your gut called the microbiome. Humans evolve so slowly that we can’t possibly keep up with the rapid evolution of microbes. So, far back in the mists of time, we recruited our own bacteria to man the front lines.
These so-called commensal bacteria can join the fight against pathogens before our immune system is even aware of the intruders. These bacteria produce feel-good neurotransmitters like dopamine and serotonin to let us know they are doing their job. They also secrete short-chain fatty acids like butyrate that both nourish and heal the cells lining our gut, keeping it intact.
A “leaky gut” can allow bacteria to enter the bloodstream, where the heart blithely pumps them to every organ in our body, including the brain. Although the blood-brain barrier keeps pathogens and toxins out, it can be compromised by chronic inflammation. This is one of several ways that gut microbes affect our mood and cognition.
Our dependence on microbes is truly humbling.
The Secrets Unveiled
So, what are the secrets of nutritional psychiatry? Is this going to be time-consuming and cost us more money? Thankfully, no. There are many templates for quality diets, including those from Okinawa, Norway, and Greece. All of these have some important things in common:
Veggies for fiber and polyphenols to feed your good bacteria, which then can protect you from pathogens.
Grains for fiber, vitamins, and minerals.
Lentils for fiber and protein.
Nuts and seeds for healthy fat, protein, and fiber.
Virgin olive oil for healthy fat and polyphenols.
Fish for protein and omega-3 fats.
As well as adding these good foods to your diet, try to reduce junk food. It tastes delicious, of course, but it is designed to be addictive, and—because it is low in fiber—it is killing your microbes.
Jacka and her team found that a quality diet actually costs less than a junk food diet. And, because they saw health care professionals less often, it saved them time, even if they had to cook a little more.
Perhaps the biggest upside is that these patients did it by themselves. They took on their own health care, and it was empowering.
What we eat can be fast medicine or slow poison. The choice is ours, and it’s on the plate in front of us.
References
Jacka, Felice N., Julie A. Pasco, Arnstein Mykletun, Lana J. Williams, Allison M. Hodge, Sharleen Linette O’Reilly, Geoffrey C. Nicholson, Mark A. Kotowicz, and Michael Berk. “Association of Western and Traditional Diets With Depression and Anxiety in Women.” American Journal of Psychiatry 167, no. 3 (March 2010): 305–11.
Jacka, F.N., O’Neil, A., Opie, R. et al. A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial). BMC Med. 15, 23 (2017).
Sudo N, Chida Y, Aiba Y, Sonoda J, Oyama N, Yu XN, Kubo C, Koga Y. Postnatal microbial colonization programs the hypothalamic-pituitary-adrenal system for stress response in mice. J Physiol. 2004 Jul 1;558(Pt 1):263–75. doi: 10.1113/jphysiol.2004.063388. Epub 2004 May 7. PMID: 15133062; PMCID: PMC1664925.
Jeff, there are some simple findings in the gut-brain field, but mostly it's terrifically complex. The Brunner's gland research shows that the gut-brain axis goes both ways: stress affects the amygdala which affects mucus production and the growth of Lactobacillus. That in turn can affect levels of stress. It's biology, so nothing is simple. Nature always goes for baroque...
Scott I love simple when it comes to the Gut-Brain Axis, but man the tsunami of press lately on the mapping circuitry and the Brunners gland involvement was some must-read stuff. But as you say, NONE of that happens without your list of foods.