Immune Systems Need to be Wired with Volume Control
The adaptive and innate immune systems are great when you are young, may need to be turned down in your sunset years…
There is evidence building that the immune system works great for youngsters, who need immunities to ward off diseases and heal injuries that prey upon developing bodies, and kinda sucks for older people, whose immune systems have run amok and almost joined the enemy. Accordingly, food intakes and exercise regimens need to be age-adjusted. Think lots of proteins for rowdy kids who are stubbing their toes, falling out of trees, getting frequent sniffles, and deluged with germs before their bodies are fully formed and have all their defenses. Think lots of fiber, less protein, less calories, sensible exercise (without tissue damage), NSAIDS and steroids (all anti-inflammatories) for older people.
Recent breakthroughs on these fronts have been the knowledge that the adaptive immune system (T-and B cells which adapt to specific diseases) in older people are weakened, and that the innate immune system sometimes overreacts later in life, causing auto-immune disorders plus unnecessary inflammation that may abet obesity, diabetes, cancer, cardiovascular disease, and Alzheimer’s. In addition to the aging process, which causes cells to eventually break down, the trigger is often overeating, or eating the wrong things (mostly overloads of carbs, bad fats, and sometimes proteins). The discovery that caloric restrictions led to longer lifespans led to the discovery that mTOR (mammalian target of rapamycin) cell receptors (essentially the things that signal the demand for food and activate insulin receptors to stimulate cell growth) were on overload in many seniors, creating a cascade of robust inflammatory agents that were inviting other diseases. While these signals were thought to be appropriate earlier in life (think back to the 1800s and earlier, when diseases ran wild and infant mortality was high due to poor diets and unformed immune systems) they began causing chronic diseases in the elderly after food became more caloric and plentiful.
Thus, there began not only the search for ways to cut calories and do appropriate exercise among seniors, but also a sort of magic pill that could turn down the mTOR response and more of less kill appetites. It turned out that there were many “natural” mTOR inhibitors, such as nicotine, caffeine and various teas, but also a naturally occurring substance, called Rapamycin (found on Easter Island) that muted mTOR, and is now used for autoimmune diseases and cancer treatments, among other things. As you might expect, turning down the immune system sometimes leaves one open to other diseases, and so these drugs are used carefully and under medical advisement. It has been theorized that Rapamycin, taken regularly by elders, may even extend lifespans by 10% or so, although no one is really sure. (Blagosklonny, 2013)
There is even a theory that people and animals are divided into “fast growing” and “slow growing” types, with the “fast growing” better adapted to surviving childhood (think athletes and bullies) while “slow growing” are better adapted to old age, provided they can survive childhood (think skinny people and nerds). The former group is thought to have a robust mTOR response that perhaps hurts them later in life, while the latter group is inclined to live longer, with a sort of built in delayed gratification.
All told, this may first mean that diet should be considered in the context of exercise and age. Younger people can generally thrive on a high protein diet (meat, eggs, dairy) provided they lead active lives. The high protein diet not only builds and repairs muscles, but a robust immune system that further protects the body from damage. Partly as preparation for later in life, portion control, carbs, fiber (whole grains, fruits and vegetables) should be considered to promote healthy digestion and provide energy for high activity.
The elderly need to eat sensibly, restrict calories, and particularly exercise often. Inflammation markers should be monitored while safe, anti-inflammatory supplements are considered
Conversely, older people (let’s say age 45 and up) need to continue exercising and exercising sensibly (low-impact, some strength, some aerobic, less damage to muscles and joints) as exercise is a major net anti-inflammatory. They need to cut down on size and frequency of meals, adding fiber, sensible fats and carbs, plus proteins. The subject of protein is somewhat controversial, since elders need to maintain muscle mass but be mindful of the dangers of too much. It’s generally recommended to have a few eggs, glasses of milk, meat portions per week but under a doctor’s advice (protein can promote inflammation and stress kidneys along with some other bad effects). The added fiber and exercise helps activate sluggish digestive tracts, while reducing calories and lowering mTOR response. Keeping cells “hungry” helps them to maintain their own fitness, clear out ineffective cells, mute inappropriate immune responses and slow the body’s clock.
It is no accident that many seniors are popping NSAIDs like crazy and/or rubbing in or inhaling corticosteroids. These two agents go a long ways towards muting the innate immune response, which not only makes us feel better but perhaps delays the onset of aging diseases. However, they have their own negative long term effects, and are thus considered secondary to sensible exercise and good diet. Natural mTOR inhibitors like coffee, some teas, and perhaps statins, curcumin, resveratrol, olive oil, Omega-3 and other substances would seem to help. Perhaps someday, seniors will also take regular doses of a drug such as Rapamycin, with another agent that helps repair our aging immune systems so that we still have appropriate defenses to disease and cell damage. But until that day, the AARP set should limit calories to 2000/day of primarily whole grains, fruits and vegetables, eat some meat and dairy but not too much, and get at least 100 minutes of low impact exercise per week. (Aliper, et al, 2017)
At age 65, I now have my C-Reactive Protein checked every year, to monitor my level of inflammation. I have managed to reduce this number to around 1 mg/l, although it is always in danger of elevating. In the future, there may be other, better inflammatory markers. There is also telemere measuring by genetics labs (telemeres being the ends of genes, the lengths of which indicate the number of lifetime cell divisions and thus your genetic age). Theoretically, a healthy 65 year old might have “60 year old telemeres”, while an unhealthy patient’s might be “70 or more”. I’m not quite ready for that one though. (Munoz-Lorente, et al, 2019)
