Okay, readers, I posted on the basics of the immune system. If you missed that post, click here to read it. Bare bones version: we have an innate immune system that immediately goes to work against pathogens, and a slower adaptive immune system that kills pathogens, remembers them, and confers immunity by producing antibodies to those specific pathogens.
Since SARS-CoV-2 is a novel (new) virus, our adaptive immune systems have nothing to remember, which explains why it is so contagious and why it is taking so many people down. We don’t know yet if this virus will mutate and evade adaptive memory. Can people get it twice? We don’t know.
In this post, I want to explore how what we eat and drink affects our immune systems.
In general, eating lots of fruits and vegetables is recommended for the fiber and nutrient density, as is moderate to no alcohol consumption. Maintaining a healthy weight is also recommended.
There’s a lot that we don’t know yet about the highly complex immune system, but we do know that malnourished people are more vulnerable to infectious diseases, as are the elderly. You of course are aware that you do not have to be living in poverty in a third world country to be malnourished. Diets high in processed foods (a first world problem) can result in malnourishment.
Micronutrients that affect immune responses
The micronutrient deficiencies that have been shown to alter immune responses in animals include the following:
- Vitamin A
- Vitamin B6
- Vitamin C
- Vitamin D3
- Vitamin E
Foods high in these nutrients are recommended, and if these foods are unavailable, supplements should be helpful. High quality multivitamin and multimineral supplements can help.
I found this cool website where you can select a micronutrient and see what foods are high in it. Did you know that hemp seeds are high in zinc? I didn’t.
Stomach acid declines with age, which impacts nutrient absorption
Older people are more likely to be deficient in micronutrients. One possible factor is that stomach acid production declines with age. Zinc deficiency, high sugar intake, and eating too quickly also contribute. Stomach acid helps break down food for digestion and absorption of nutrients.
A way to remedy this is to take HCl, hydrochloric acid, with meals. Chewing food thoroughly, limiting processed foods, eating fermented foods, drinking apple cider vinegar in water, and eating ginger are recommended ways to boost stomach acid production without taking an HCl supplement.
The gut microbiome influences the immune system, and vice versa
Seventy to eighty percent of immune cells are found in the gut. The gut microbiome provides antigens and influences immune system cells. Food is a foreign substance introduced into the body, and the immune system decides if it’s beneficial or a threat. These two systems regulate and support each other.
When all is well, the immune system helps maintain stability of beneficial gut microbes, and microbes support the development of immune cells, as well as fine-tuning immune responses.
Keeping the gut microbiome healthy includes:
- Not taking antibiotics unless absolutely necessary,
- Consuming prebiotics — nondigestible fiber feeds the health-producing gut bacteria. Eat lots of veggies and fruits for fiber.
- Eating fermented foods like sauerkraut, yogurt, and beet kvass increases beneficial micro-organisms in the gut.
Improving gut health and reducing gut inflammation (leaky gut)
One concern about the modern diet is that it may produce systemic inflammation through gaps in the cells that line the small intestines. This is called leaky gut, or intestinal permeability. These gut lining cells produce the anti-microbial chemicals that are part of the innate immune system.
Here are some recommendations to reduce gut inflammation:
- Avoid processed, high fat, and high sugar foods.
- Avoid common allergens, such as wheat and dairy.
- Avoid alcohol.
- Investigate a low-FODMAP diet.
- Add foods with probiotics (kefir, yogurt, kimchi, etc.) and take probiotic supplements.
- Add foods with prebiotics (bananas, berries, etc.). Prebiotic supplements are available.
- Reduce your use of NSAIDs.
- Reduce your stress level.
- If you smoke, quit.
Working with a nutritionist can be very helpful.
This is Day 7 of sheltering in place in Austin, Texas. Here’s our case count as of last night. We’ve had another death. We’ve been getting roughly 20 more known cases per day.
Expect the case count to go up quite a bit tonight. There’s a report that a group of 70 people (mostly UT students) in their 20s went to Cabo in Mexico for spring break a week and a half ago, and after returning to Austin, 28 of them have tested positive, so far. About half the cases in Austin are still those ages 20-40.
Here’s a poignant video showing the empty streets of normally bustling Austin. The sentiment at the end says it all.