JAN 27

3. JAN 27

Assigned Work

• Sonnenbergs, C 6, "A Gut Feeling"

In-class

• Practicality: Comments on food budgets and variety
• Satisfaction/Practicality/Nutrition: A 50cent egg lesson - $10/loaf bread.

The NSP Model for Dietary Change: What Should your Food Budget Be?

• 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.

The NSP Model for Dietary Change: Three 50cent egg lessons

• A $10 loaf of bread?
• Quality differences in pineapple.
• Ultra-processed tomato sauce [3] v. canned, imported from Italy [4]

The NSP Model for Dietary Change: Comparing notes on variety expectations

• Today we will start discussing how the NSP model helps us think about dietary change.

• Nutrition, Satisfaction, Practicality and Dietary Change

• General “false practicality” point: How practical is the drive-through fast food option? How much time does it take? How does it makes you feel while eating, after eating? Do you notice blood sugar spikes from ff? How long until you feel hunger again?

• Small group exercise. Today we’ll focus on some “Satisfaction-Practicality” connections relevant to designing / re-designing your diet. Specifically, consider these questions as you head into small group discussion to hear others’ approaches and thinking.

• How much variety do you expect from breakfast, lunch, and dinner? Make a list.

• How many different dinners would you need in your repertoire to feel like you had plenty of good choices? What is involved in "provisioning" those dinners?

• Types of variety:

• I want to come home knowing that I can choose from X different dinners depending on mood and conditions. (Home menu model)
• I want my shopping to give me X dinners to choose from. It’s ok if variety decreases as the week goes by. (Variety Shopping model)
• I’m ok scheduling each dinner by the days of the week. (Days of week meal planning.)

• Other variety considerations:

• I don’t want to repeat meals much within a week.
• I’m fine eating the same thing for 2-3 nights or alternating 2 dinners over 4 days.
• I look for variety seasonally.
• I can eat the same breakfast for months, but then I need to change it.

• Other sources of variety

• Seasonal rotations -
• Preparation variety - three pastas - tomato, primavera, ceci(!).
• Make-shift dinners. (I can sometimes just make a salad and side veg for dinner.) Note the nutrition/practicality issues here. Easy to do and very practical if you are on top of your nutrition. You could add a protein shake.

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. [5] 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.