JAN 29

4. JAN 29

Assigned Work

• Sonnenbergs, C 6, "A Gut Feeling"

In-class

• Review of Food Bios
• Practicality: Comments on food budgets
• Satisfaction/Practicality/Nutrition: A 50cent egg lesson - $10/loaf bread.

From Food Bios

• Lots of very interesting stories and representations here. Thanks. Here are a few excerpts:

• There is just something about cooking or baking in an empty kitchen, just with yourself, some good music, and preparing a good meal, that has always felt like home to me.

• I enjoy listening to music when I cook or talking with my roommates. I think there is a social aspect to cooking and enjoying meals with those around us, and this is something I appreciate about food.

• Now as a senior in college, I am lucky if I eat one real meal a day. I find myself critiquing my body so much that I don’t get hungry that often

• Food is love. This is something often observed and said in my house, and therefore is ingrained into my relationship to food

• When I go home and get to sit at the dinner table with my family, having an enjoyable conversation and satisfying my hunger with a home-cooked meal, a very distinct joy and peace is present.

• Throughout my life I have had different relationships with food and my food journey has changed

• When I think about my relationship with food, it seems boring. I tend to only eat out of necessity or because I have to get through the day

• My personal relationship with food and eating has gone through significant changes throughout my life - in some moments feeling very secure in that relationship, others having a very challenging and difficult relationship with eating

• The complexity of my relationship with food arises from personal issues with body image and the consistent negative talk about certain groups of food

• I am currently stuck in a situationship with food. Ever since I started living on my own, I feel like I am never able to fully commit to a regular, stable, and balanced eating habit.

• Food has always played a large role in my life. To me, cooking and cuisine is a personal interest, strengthening agent in my relationships with loved ones, and as a coping mechanism for anxiety.

• I am a food lover. I love pretty much any kind of food, except for sushi and unusual animal organs, but am adventurous when it comes to food and willing to try just about anything.

Practicality: Comments on Food Budgets

• Some country comparisons: [1] and within the US: [2]. Generally, American's spend under 10% of disposable income on food vs. about 14-17% for Italians, French, etc. These are rough comparisons because of wealth effects and geographic effects. Norwegians are wealthier than Americans, Italians a bit less wealthy, but Mediterranean cultures have closer access to inexpensive fresh food.
• At $20/hr, if you spend 14% of net monthly income on food, you would have about $400 to spend. You also use this figures to think about what a just or "living wage" would be. That $20 wage certainly cannot fund high rent prices and a healthy plant based diet.

Satisfaction/Practicality/Nutrition: Two 50cent egg lessons

• A $10 loaf of bread?
• Quality differences in pineapple.

The Enteric-Central Nervous System Axis

Sonnenbergs, C 6, "A Gut Feeling"

• The Brain-Gut Axis

• Documents the two-way comm bt brain and gut (enteric nervous system). Gut brain is "listening" in on the trillions of microbes in the gut.

• Central nervous system (sympathetic and parsympathetic). Autonomic functions like heart rate include "transit rate" of food, secretion of acid in stomach and mucus in intestines. Hypothalmoic-ituitary adrenal axis (HPA) controls hormones that affect digestion.

• Gut bacteria can influence our perception of the world and behavior:
• serotonin production
• toxplasma gondii (rodents and cats)
• microbe free mice are bigger risk takers. Critical phase in correcting for this.
• mice with impaired microbiota had worse memory (141)

• Speculate symbiotic relationship -- microbes likely improve fitness through risk aversion and memory.
• Mechanisms -- gut bacteria produce chemicals that go into blood stream.

• The Personality Transplant

• More evidence of effects on perception and behavior:
• 2011 McMaster study: fecal transplants between anxious and gregarious strains of mice partially reversed behavior. Mechanisms: Brain-derived neurotropic factor (BDNF) - associated with depression, schizophrenia, and OCD. Gregarious mice has increase in BDNF after transplant. Intermediate mechanisms not completely clear. "How can a bacteria at the end of your digestive tract change the expression of a protein at the top of your skull?"

• An unsupervised drug factory

• 144: MACS (microbiotically available carbs) produce SCFAs, but also many other compounds, including toxins that normal kidneys filter. Lots to learn. Some stimulate appetite. Many products may be neutural with respect to fitness. They imagine a hypothetical scenario in which a pectin digesting bacterium takes up residence in your gut. Maybe it has mutated to also stimulate your desire for fruit.

• The Microbiota's Toxic Waste

• Hepatic encephalopathy -- treatments target microbes that produce toxins. Earlier treatments required removing some length of intestines.
• TMAO - trimethylamine-N-oxide. produced by microbes. implicated in cardiovascular disease. Red meat and fatty foods increase TMAO. Vegans and vegetarians have low TMAO production. Study on long term vegan who eats a steak. Still low TMAO. Might be lacking those microbes. (might argue for low meat consumption as nearly healthful as total meat abstinence).

• Two-way communication between "brains"

• Stress, IBS, Autism, and angry faces
• Induce stress in mice and their microbiota change. Threats cause symp n.s. to do lots of things, including slowing motility and digestion. (maybe to prep us for action)
• Some stress events have long term effect on microbiota. 150
• IBS - read - could be a stress induced imbalance that is hard to correct because it gives you MB that also induce stress. also heightened pain perception. Read at 151.
• Some evidence in animal models that probiotics can help with psychological problems (psychobiotics). Some studies in humans suggest this as well. Better studies needed.

• Chemical spills out of the gut

• ASD - autism spectrum disorders. Increasing dramatically. Often associated with gut symptoms. [3] Note connection to rise of industrial diets!
• ASD research: 2013 Caltech studies by Mazmanian - looked at maternal immune response to infection during pregnancy. Treatment with b. fragilis helped somewhat in mice, both with leaky gut and behavioral symptoms. Effect might involve other microbes. B. fragilis affected over 100 other compounds in blood. Human/mice diffs are significant here. Caution.

• Fermented Foods

• 2013 UCLA fMRI study on probiotic yogurt and response to negative facial emotions.