What Health Advice Is There a Consensus On?

What recommendations related to diet, nutrition and health seem to be universally agreed on by experts of nearly all stripes and schools of thought?

Given the incredibly high levels of disagreement in these areas, and the poor quality of studies, it often seems like we know almost nothing.

Below is my attempt (via a combination of brainstorming and crowdsourcing) to list what there does seem to be a high rate of consensus on. Please let me know if you notice any mistakes.

Tentative List of Universally Recommended Health Interventions

(1) Don’t consume a lot of sugar (at best, it’s “empty calories” and could lead to tooth decay. But some claim it is much worse than that).

(2) Exercise regularly – it’s best to rotate which type of exercise you do, being very careful to avoid injury, especially when you are getting into new forms of exercise. (It is less clear what forms of exercise are best for long term health, e.g., strength training vs. cardio, and it’s less clear quite how much exercise you should get – also, extremely high levels of exercise are believed to be associated with increasing some health risks, for instance doing Iron Man triathlons).

(3) If you are going to eat a lot of carbohydrates, generally you should choose complex carbs over simple carbs (usually whole grains are also recommended over refined grains, but some argue that whole grains should be sprouted/soaked to remove parts of the seed that are designed to protect it from digestion.)

(4) Brush your teeth with a fluoride toothpaste at least once per day (though perhaps it is not actually a good idea immediately after eating, especially if you’ve been eating acidic foods). The suggestion is to brush before breakfast or wait an hour after eating, and beware of brushing too often or too vigorously. Brushing twice per day may be better than brushing once. Also, note that a VERY small percentage of healthcare professionals are anti-fluoride.

(5) Hydrate regularly throughout each day, as soon as you feel thirsty, but before you are likely to feel thirsty as well (since thirst indicates that you may already be dehydrated, so you want to pre-empt feeling thirsty). Hydrating with water is the safest bet, though it’s not clear how much liquid you need in total (the 8 cups of water a day theory seems to be bullshit). It also is unclear whether it’s important to do this with water, or if other drinks, like unsweetened tea, are acceptable replacements. Hydration may also be good for your teeth by reducing dry mouth – some argue that even mild dehydration can negatively impact mood and performance.

(6) Eat plenty of vegetables (preferably not deep-fried ones – note also that there do exist a very small number of people in the health field who advocate an essentially zero-carb or meat only diet).

(7) Don’t eat a lot of deep-fried foods in general.

(8) Take Vitamin D3 supplements if you are >60 years old and don’t get a lot of outdoor time, or if you are in the general population, take them if you get very little sunlight.

(9) Avoid frequently drinking large quantities of alcohol.

(10) Avoid frequently consuming tobacco products (but since many of them are addictive, that means it’s safest to avoid them altogether).

(11) If you have the ability to make yourself lose weight and keep it off, you should try to lose weight/reduce body fat if you have a very high body fat percentage, or if you have a lot of body fat around the gut area (the extent to which mild to moderate obesity is bad per se is somewhat debated, as in some studies mild levels of obesity were sometimes even correlated with better health outcomes) – avoiding metabolic syndrome and poor blood sugar dysregulation may be more necessary than avoiding a very high body fat percentage though the two are significantly correlated – note also that lots of data suggests that three years after a diet most people have regained the weight they lost, and some say that regularly cycling your weight by losing then gaining then losing again could be unhealthy (so the value of a blanket “lose weight when obese” recommendation is questionable).

(12) If you are going to eat something sweet, a piece of fruit is a better bet than candy or sugary baked goods.

(13) Avoid consuming trans fats.

(14) Don’t consume excessive amounts of mercury (which is found in many fish – some say that tuna, king mackerel, marlin, orange roughy, shark, and swordfish are particularly worrisome).

(15) Don’t eat a lot of foods that are burned to the point of being severely blackened (at best burning tastes bad and destroys the nutrients in food, at worst, it might increase the chance of getting cancer, it’s unclear).

(16) Spend some time outdoors in the sun each week.

(17) Avoid getting frequently sunburned (especially avoid severe sunburn, e.g., blistering).

(18) If you are unusually low in any vitamin then you should consume more of it (but if you have relatively normal levels, there is not a consensus on whether you should have more of any vitamin, except perhaps Vitamin D for the elderly which seems to be basically agreed upon – there is also disagreement about whether vitamin pills are as effective as vitamins from whole foods, or in which cases you should take sublingual dissolving vitamins or vitamin shots instead of pills).

(19) If you are a strict vegan, take vitamin B12 supplements (while only a very small amount of B12 is needed by humans, it is not reliably found in plant-based foods).

(20) Don’t get addicted to any drugs (prescription or non-prescription) other than perhaps caffeine.

(21) Don’t run an increasingly large sleep deficit (though the amount of sleep each person requires to avoid a deficit seems to vary considerably).

(22) Wash your hands with soap regularly (though some claim that special anti-bacterial hand soap is not a good idea)

(23) Don’t regularly have non-negligible amounts of caffeine within a few hours of going to bed (though people’s sensitivity to this seems to vary a lot – some people may be able to get away with it, but on average it impairs sleep quality).

(24) Avoid long stretches of inactivity (i.e., take breaks where you move around).

(25) When typing, avoid having your wrists bent at a significant angle for long periods, avoid having to bend your neck substantially downward or upward to see your computer screen, and avoid sitting with your back hunched forward for long periods (some people find that using a vertical mouse helps if you have wrist pain, and some people report benefits from using a laptop stand to raise your laptop to a more reasonable height).

(26) Each week spend at least a bit of social time with people you get along well with.

(27) If you have very high levels of anxiety, depression, or hopelessness, you should seek treatment as soon as possible (e.g., you could try Cognitive Behavioral Therapy with a psychologist, go to a psychiatrist to try antidepressants, or take up a Mindfulness-Based Stress Reduction practice).

(28) Eating a diverse range of healthy foods is usually better than eating a narrow range of foods (of course, a diverse range of unhealthy foods is still unhealthy).

(29) Avoid very high doses of certain vitamin and mineral supplements where overdoses are known to happen (e.g., Iron supplements, vitamin A and vitamin B-6 – beware of mega-dose vitamins in general unless you know what you’re doing, as they are unlikely to be helpful and could be harmful).

(30) If you have a broken bone or reasonable sized cut or scrape that appears as if it could be infected, go to a doctor immediately (some broken bones require splinting to heal properly, infected wounds may become dangerous without proper treatment).

(31) If you have a mole that violates the ABCDE rule, get it checked out by a dermatologist immediately. That means you should get it checked out if it has: Asymmetry (if one side of the mole doesn’t match the other), Border irregularity, color that is not uniform, Diameter more than 6 mm (which is about the size of a pencil eraser), and Evolving size, shape or color.

(32) Highly processed meats (e.g., hot dog or bologna) are worse for you than less processed ones.

(33) Do things to keep your brain active, such as learning something new each week or doing something that is mentally taxing.

(34) If you have high levels of stress, try to reduce them using whatever techniques you find effective (high stress has been linked to various negative indicators in the body – techniques that some people find effective to reduce stress include Cognitive Behavioral Therapy (CBT), meditation, progressive muscle relaxation, yoga, walking in nature, cuddling with a pet, or exercise that keeps your heart rate elevated for a reasonably long period).

(35) Keep your sleep cycles at least roughly in sync with the dark/light cycle of the planet (i.e., do most of your sleeping at night, and live most of your waking hours during the day).

(36) Don’t regularly drink alcohol before going to bed (as it is known to cause poor sleep).

(37) If you think you may be suicidal, or you have made plans for how you might commit suicide, you should call a suicide hotline immediately, and afterward make an appointment with a therapist or psychiatrist to see them as soon as possible (and tell this person about your suicidal thoughts).

(38) Keep your living environment at a comfortable temperature, generally in the 65-75°F (18-24°C) range.

(39) If you’ve had pain in your mouth or teeth for more than three weeks, go to a dentist!

(40) Wear your seatbelt every time you are in a car. (Even if it’s a short ride, do it anyway, because, if you don’t, you are eroding the seatbelt wearing habit – also, a note for New Yorkers that even car accidents in taxis can hurt you badly when your face hits the glass in front of you.)

(41) Folic acid supplements for women who are or may be pregnant (to help avoid birth defects).

(42) Either keep health insurance, or live in a country where health care is universal, or keep enough savings that in a medical emergency, you can get the treatment you need.

(43) Don’t drive when drunk or high on drugs, or be in a car driven by such a person.

(44) Don’t send text messages or do other distracting things while you’re driving, or be in a car driven by someone who is distracted.

(45) If you are depressed, bi-polar, or potentially suicidal, don’t live in a house that contains a gun (or other easy means of suicide).

(46) Always use condoms when having sex with new partners if they have not been recently screened for STIs.

(47) Always use some form of birth control when having heterosexual intercourse unless you are planning a pregnancy.

(48) Women should avoid wearing tampons for more than 8 hours at a time to reduce the risk of Toxic Shock Syndrome. (Some say that the lower the absorbency of the tampon the lower the risk)

(49) If you have a severe bacterial infection, take antibiotics. (Note that the type of bacteria and antibiotic matters.)

(50) If you have diarrhea, continually drink oral rehydration solution (however if you have severe dehydration or are vomiting, seek medical treatment – you can make your own oral rehydration solution using 6 ‘level’ teaspoons/25.2 grams of sugar and 0.5 teaspoon/2.1 grams of salt in 1 liter of water – or you can drink Pedialyte – diarrhea is actually surprisingly dangerous, so stay hydrated!)

(51) If you are taking antibiotics, and you are not immunocompromised, then take a probiotic with the antibiotic to reduce the chance of antibiotic-induced diarrhea. (Note that there is a lack of consensus on the amount and type of probiotic to take).

(52) Eat foods containing fiber. (Sometimes about 30g per every 2000 dietary calories is recommended, but recommendations vary)

(53) Don’t live or work in a place where people regularly smoke indoors.

(54) If you are a women who is planning on having children, try to have them before you reach age 40 (the younger you do it, the safer it is for you and the baby, though with advances in early screening many problems associated with pregnancy at an older age are now caught – fertility also increasingly becomes a problem with age).

(55) Avoid exposure to asbestos and lead paint.

(56) If you live in an area with disease-carrying mosquitos, use a mosquito net on your bed when you sleep.

(57) If you have sudden and severe symptoms of illness that do not resemble a cold or flu, or unexplained symptoms of illness that continue for a long time, go to a doctor.

What else should be on this list that I missed? What am I mistaken about that I should remove from this list (because there is actually some disagreement among experts)?

Also, here are some other health and nutrition questions that didn’t make this list because, while many advocate strongly for one side, there still seems to be a reasonable amount of disagreement (rightly or wrongly):

Important Health Questions Experts Don’t Seem To Have Consensus On

(a) How bad is saturated fat, if at all?

(b) How useful is omega 3 supplementation, if at all?

(c) How bad are carbs versus other macronutrients?

(d) Is there any benefit (or harm) to getting more than the RDA of protein (0.36 grams per pound of body weight)?

(e) Is flossing truly effective? (If you like flossing, or at least don’t mind it, it may well be worth it, but the benefits are not as clearly established as one would ideally like, and there have been some claims, possibly false, that it can cause bacteria to escape from your mouth into your body in a way that could be bad)

(f) Does dietary cholesterol lead to high blood cholesterol? (apparently, the FDA just released new guidelines on this that say “no.”)

(g) Is blood cholesterol correlated enough with bad outcomes that we should care about it, per se?

(h) What types of preventative screening/testing should everyone routinely get?

(i) What dietary supplements (if any) should a healthy person take?

(j) Is there any harm from Aspartame or other artificial sweeteners like Splenda? (all of the many randomized controlled trials on Aspartame on humans I’ve looked out found no negative effects except headaches in a small subset of people, but other studies in rats show weird effects that are hard to interpret, and a lot of people are anti-Aspartame without providing clear reasons – note that sugar alcohols like Sorbitol cause temporary digestive problems for some people.)

(k) Is polyunsaturated fat good for you, bad, or neutral?

(l) How bad is meat for you as a broad category, or is it too broad a category to generalize?

(m) How much should you limit your salt intake, and do moderate levels of salt intake actually increase blood pressure (outside of the rare group of “salt-sensitive” people)?

(n) Which type of cooking oil (e.g., olive oil, coconut oil, avocado oil, etc.) should you use or avoid?

(o) How much exercise is ideal, and of what forms? [as Stuart Buck points out: “If the goal is to be strong and build muscle mass, lift weights. If the goal is to be fast, agile, etc., work out more like a sprinter and/or a professional basketball player. If the goal is aerobic fitness and endurance, do lots of long runs or swims, etc. But for long-term goals like longevity, that’s where we don’t have rigorous evidence (too much selection bias)”]

(p) Is going into ketosis (by lowering your carb intake dramatically) a good or bad idea? (Many doctors think it is not a healthy state to stay in for a long time, but anecdotally some people who do this diet swear by it)

(q) Is intermittent fasting a good idea?

(r) Is it important to go to bed/wake up at the same time every day?

(s) Is there any real benefit to eating organic foods?

(t) Are “grass-fed” animal products healthier than non-grass fed ones?

(u) Is there any real difference (in your body) between sugar and high fructose corn syrup? (common sense about chemical composition and some studies suggest the answer is that there is no difference, but many people think high fructose corn syrup is worse)

(v) What’s the optimal mix of macronutrients?

(w) Do metformin, rapamycin, resveratrol, human growth hormone, blood transfusions from young people, basis (nicotinamide riboside and pterostilbene), or other NAD boosters increase lifespan for healthy individuals?

(x) Are GMO foods actually risky, or are they fine?

(y ) Is the heuristic of eating “natural” or “whole” foods actually accurate, or does it exclude too much?

(z) Are probiotics (like acidophilus) useful to take for a generally healthy person?

(aa) How important is stretching, what type of stretching (static vs. active) is best, and when should you do it (just before you exercise, just after, or at other times)?

(ab) How bad are pesticides on our foods (which types are bad, and how much of them do we have to consume before problems begin)?

(ac) Should you take a multivitamin pill? (the tide has been turning against them as repeated studies fail to find a benefit in healthy people, but some experts still recommend them – also for water-soluble vitamins, we seem to pee most of it out when we take large doses)

(ad) Are there vitamin/mineral deficiencies that a significant proportion of people in developed countries have? (e.g., possibly magnesium, potassium, choline, D3, K2)

(ae) Is it helpful to wake up when the sun rises each morning?

(af) Do heavily calorie-restricted diets improve longevity in humans (like they do in mice)?

(ag) Is using mouth wash (like Listerine) good for your oral health?

(ah) Is donating blood (for men and women who don’t menstruate) good for health?

(ai) Does zinc or echinacea reduce the severity or duration of colds when taken daily or when taken at the onset of symptoms?

(aj) Does the source of calories (e.g., from carbs, fat, or protein, with fiber or without) matter significantly when it comes to non-water body weight change (or does a calorie have the same effect regardless of the source when we are talking just about weight change and excluding water weight)?