There is a lot of bad science and controversy in the realm of how to have a healthy lifestyle. Every week we are bombarded with new studies conflicting older studies telling us X is good or Y is bad. Eventually we reach our psychological limit, throw up our hands, and give up. I used to do this a lot. I knew exercise was good, I knew flossing was good, and I wanted to eat better. But I never acted on any of that knowledge. I would feel guilty when I thought about this stuff and go back to what I was doing. Unsurprisingly, this didn't really cause me to make any positive lifestyle changes.

Instead of vaguely guilt-tripping you with potentially unreliable science news, this post aims to provide an overview of lifestyle interventions that have very strong evidence behind them and concrete ways to implement them.

A quick FAQ before we get started

Why should I care about longevity-promoting habits at a young age?

First, many longevity-promoting lifestyle changes will increase your quality of life in the short term. In doing this research, I found a few interventions that had shockingly large impacts on my subjective day-to-day wellness. Second, the choices you make have larger downstream effects the earlier you get started. Trying to undo years of damage and ingrained habits at an advanced age really isn’t a position you want to find yourself in. Third, extending your life matters more the more you believe in the proximity of transformative tech. If the pace of technological improvement is increasing, then adding a decade to your life may in fact be the decade that counts. Missing out on life extension tech by a few years would really suck.

Isn’t longevity mostly just genetics?

That's what I believed for a long time, but a quick trip to wikipedia tells us that only 20-30% of the variance in longevity is heritable.

What sort of benefits can I expect?

The life satisfaction of people who remain independent and active actually increases significantly with age. Mental and physical performance are strongly correlated, meaning maintaining your body will help maintain your mind. The qualitative benefits for life satisfaction of many of these interventions can be so dramatic that it is hard to estimate them. The gulf in quality of life between people maintaining good habits and those who do not widens with age.

How were these recommendations generated?/Why should I believe you?

This post summarizes studies at the intersection of having large effects, large sample sizes, and being well-designed in terms of methodology. The cutoff for an intervention being “worth it” is somewhat subjective given that there is often only a rough estimate of the overall effect sizes of various interventions in comparison to one another. CDC mortality statistics were used to determine the most likely causes of death in various age brackets. The list of things that kill people balloons significantly as you get towards the less common causes of death and I have limited research time. Individuals who face unusual health circumstances should of course be doing their own research and consulting health professionals.

This brings me to my disclaimer:

This post is not intended to diagnose, treat, cure, or prevent any disease. No claim or opinion on these pages is intended to be, nor should be construed as medical advice. Please consult with a healthcare professional before starting any diet or exercise program. None of these claims have been evaluated by the Food and Drug Administration. Suggestions herein are intended for normal healthy adults and should not be used if you are under the age of 18 or have any known medical condition.

Alright, let’s dive in.

Things that will eventually kill you

CVD

At the top of our list is cardiovascular disease, or CVD, causing the plurality of all deaths by far. We will break down the controllable components of CVD in terms of lifestyle interventions.

Smoking

This doesn’t need much of an explanation. Responsible for the majority of lung cancers, respiratory diseases, and a huge contributing factor to CVD. Buying an e-cig for yourself or people you know who smoke are possibly the single cheapest intervention for adding years to life. E-cigs have very high success rates in getting people to quit smoking and are absurdly cheap. You can spend under $10 and add 14 years to someone’s life. I buy them just to give away. Recommended products: 1, 2.

Alcohol

Some controversy over possible benefits of small amounts, but large amounts definitely bad. Avoiding alcoholism is a whole subject I won’t tackle here.

Blood Pressure

Second to tobacco in effect size. Blood pressure is one of the things most people ignore. It is extremely cheap and easy to start monitoring your blood pressure, and there are things you can do if you find it to be high. You want your blood pressure to be about 120/70. If you are higher than this there are some simple things you can do. The first is to exercise and eat fish every week, especially salmon. There are also a few supplements that have been found to be helpful.

A quick note about my criteria for inclusion for supplements: I am extremely dubious as to the benefit of most supplements. Study after study shows that most of them are a waste of time and money. The fish example given above is a good illustration. You might ask why you can’t just take fish oil pills. Well it turns out that fish oil pills suck, and you’d need to take approximately 9 times as much to have the same effect as eating fish, at which point they’d have dangerous blood thinning effects. So when I recommend a supplement it has to meet a pretty stringent list of requirements.

1. Large effect seen in multiple randomized controlled trials.

2. Therapeutic dose is a tiny fraction of the toxic dose, or no toxic dose able to be identified because it is so high.

3. Side effects comparable to placebo.

4. Dose size is commensurate with an amount it would be reasonable to ingest in natural form.

So basically I weight any downside risk very heavily given the spotty track record of the general reference class of supplements.

So what passes these criteria for blood pressure?

1. CoQ10, large effect size in multiple studies

http://www.ncbi.nlm.nih.gov/pubmed/14695924

2. Flavonoids/anthocyanins, these compounds are present in things like dark chocolate, fruits, and teas.

http://ajcn.nutrition.org/content/88/1/38.short

3. Garlic

http://www.biomedcentral.com/1471-2261/8/13/

I have personally had success lowering my blood pressure from the 140’s to the 120’s with these supplements keeping my exercise levels constant.

Blood lipids (cholesterol)

Here the conventional recommendations appear to be wrong, or at least somewhat misguided. First, some theory. Blood lipids are composed of a variety of substances, but for our purposes we will stick to the ones tested for in blood panels and how to interpret these numbers. A typical blood panel will report LDL, HDL, and Triglycerides. The simple story of “high LDL bad” does not accurately reflect risk of CVD. The most powerful predictor of CVD in terms of blood lipids is the Triglycerides to HDL ratio.^{[1][2][3][4][5]} The higher the triglycerides and the lower the HDL, the greater the risk. This relationship holds independent of LDL levels, which are usually the focus of cholesterol discussions with health practitioners. As it turns out, there are actually two types of LDL, and distinguishing between them is something not usually performed on a blood test. The reason for the prolonged confusion arises from the correlation between a poor HDL:Triglyceride ratio and prevalence of the unhealthy type of LDL. As a result, potent cholesterol lowering drugs are over prescribed. For people with a healthy ratio of triglycerides:HDL, a total cholesterol between 200-220 (traditionally considered “high”) is actually  correlated with lower mortality,^[6] and aggressive lowering with drugs resulted in worse health outcomes. This is not to say that statins (cholesterol lowering drugs) are not useful. On the contrary they seem to be highly helpful for patients recovering from a cardiovascular event, but they have shown no benefit for people with no history of problems.^[7] Statins have serious side effects^[8] and should not be taken lightly. Be skeptical.^[9]

So how does one go about lowering their triglycerides and raising their HDL? Again, exercise and eating fish are awesome here. Excessive fructose intake raises triglycerides, and this relationship is worsened by high BMI. Fiber and resistant starch from fruits, vegetables, and tubers has a positive effect. Intermittent fasting has also shown promising effects here.

BMI/Obesity

There are some controversies here I don’t really want to get into the details of as it is a complex subject. I do want to mention that health interventions should not have an excessive focus on whether one is losing weight. Many of the interventions discussed here have significant effects (for example on insulin sensitivity, c-reactive protein, and fasting blood glucose) even when body composition does not change. Getting BMI below ~27 should be a priority however, as it has wide ranging effects across all other interventions.

Nutrition

This is a big subject, and we’re not even going to attempt to go into detail. This section will focus on the largest high level features of a diet that have positive or negative impact. Processed meat consumption has the single largest negative effect on health. It is shockingly bad, even if you already suspected as such.^[1] In contrast, a bit of red meat has actually been found to be neutral. It seems to be that many earlier studies claiming harm from red meat did not adequately separate out the huge effect size of processed meat. Fish and nut consumption appear to be a grand slam for CVD in particular and also just for overall health.^[2][3] Pescetarians live significantly longer than vegans,^[4] lending support to fish consumption. Outside of specific foods, common micronutrient deficiencies have been indicated in everything from cancer, to immune system suppression, to poorer physical and mental performance, to sleep problems, greater inflammation, and even depression. Really there’s too much material there to cover, there are just pages and pages of studies.

There’s also the bad news that multivitamins mostly don’t do anything. There has not been found an alternative to eating a variety of nutrient-dense whole foods. Though vitamin D supplementation appears to be quite beneficial. Another LW user, John_Maxwell_IV, and I are trying to make this easy with our startup MealSquares.

Blood donation

The studies related to this have some methodological issues but overall the effect size is so large, and the cost and risks so low, that it is worth inclusion. Several studies have indicated that, for men, regular blood donation results in a massive reduction in heart attack.^[1][2][3] Other studies have found no such relation.^[4] There are also additional health benefits to blood donation.^[5] These are just some of the studies on this subject, but on balance after reviewing the evidence, I can say that donating blood once a year is almost certainly worth it if you're a man.  Donating too often is probably bad for you though.

Exercise

This topic is large enough that I am separating out my actual recommendations into another post and purely discussing the health benefits here. Exercise is probably the single most important lifestyle intervention. Even minimal amounts of exercise have very large impacts on longevity and health. We’re talking even walking 15 minutes a day causing people to live longer. Even ignoring quality of life you are looking at a 3-7 fold return on every minute you spend exercising in extended life,^[1] perhaps even exceeding that if you are making optimal use of your time. Exercise has a positive impact on pretty much everything that contributes to mortality. I don’t really know how to convince you, the reader, that the future actually exists and that future you will be incredibly angry or sad that you didn’t put in a small effort now for a better life later. But everyone has already told you this your whole life. So I’m going to contrast it with the inverse. Most of the activities that we associate with fun and leisure involve some aspect of physicality, even if it’s just walking around with friends. Losing access to these activities as can and does happen to people represents a massive decrease in quality of life. If you are reading this and you are young, you are able to simultaneously ignore your body’s need for exercise, and demand performance of it when necessary to enjoy yourself. This will not remain true forever. Exercise has a protective effect against exactly the sorts of degenerative injuries that deprive people of their freedom of movement and activity.^[2] I don’t care if you start with an exercise habit of one pushup a week, but you must do something.

Let’s move on to some relevant considerations assuming you want to exercise. What sort of exercise should I be doing? Several studies have indicated that endurance athletes enjoy the greatest improvements in longevity. I would agree with this but caution that often the groups in such studies with the best health outcomes are those that do engage in resistance training as well. Soccer and other team sport players, for example, often perform resistance training as part of their overall conditioning. This seems to be overlooked because they do not perform it at the same level of intensity as athletes in the power sports. Long distance skiers and bikers also generally train lower body strength moves at an impressive level compared to the general public, even if it is a level significantly below that of power athletes (e.g. here is an example of a training regime for a competitive skier). My point is simply that you shouldn’t read a study that says “endurance athletes live longer” and assume that all you need to do is run. Strength training also has significant effects on insulin resistance, resting metabolic rate, glucose metabolism, blood pressure, hormone balance, joint health, organ reserve, depression, increases in HDL, reduction in back injuries, sleep quality, and a variety of harder-to-quantify quality of life improvements.^{[4][5][6][7][8]} I go to the trouble to cite resistance training so heavily because I feel that the benefits of cardio are generally well-understood, but I regularly encounter the idea that resistance training is only for people who want to look like a gross bodybuilder.

Hopefully I have established that one should do both endurance and resistance training. Program specifics will be included in the other post as well as info on when benefits taper off.

Edit: Exercise post is up here.

Stress

Stress affects almost every system in your body. It increases disease risk by acting as an immunosuppressant. It directly impacts blood pressure, sleep problems, skin conditions, anxiety, depression, and even heart problems. Chronic untreated stress is often considered a causal factor in many other ailments people are medically treated for. Stress often goes untreated because alleviating it is seen as low priority. Whatever we are doing right now is worth a little stress. This can be true, but over a longer time horizon failing to learn better ways of managing stress really harms us. To confront stressors you must confront ugh fields. Non-productive coping mechanisms are the norm here: procrastination, abuse of substances including food, sleeping too much, blame as a curiosity-stopper etc. Simple strategies for dealing with low level stressors include things such as meditation, gratitude journaling, reflecting on and updating goals, or even just paying other people to deal with a recurring source of stress. Two previous LW posts have excellent advice in this area: How to Be Happy and Be Happier.

If you are depressed and don't know where to start on getting help please take a look at Things that sometimes help if you're depresed.

Supplements that impact stress include

1. Rhodiola Rosea: http://www.sciencedirect.com/science/article/pii/S0944711310002680

2. Ashwaghanda root, which shows promise for chronic anxiety: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573577/

Sleep

Chronic insomnia is a massive source of stress for many people and poses a huge mortality risk. In one study, people who got chronically less sleep had 3 times the mortality risk as people who slept well!^[1] You cannot afford to not start optimizing your sleep. It is important that your sleeping place be a quiet, dark, cool environment. You can use simple methods to improve each of these parameters. Forehead cooling has shown great promise in clinical trials.^[2] You can accomplish this with a gel pack that is cool (not ice). Even small LED lights in your room impact sleep quality because the melatonin production system is very fragile and sensitive to light.^[3] Get tape and cover lights. Try orange glasses to prevent blue light from destroying your endogenous melatonin production after 10pm. Regularize your sleeping and eating schedules. Expose yourself to bright lights in the morning to calibrate your circadian rhythms. Afternoon/early evening exercise is beneficial in making you sleepy. Melatonin pills work for many, but make sure you start with 75mcg (cut these into fourths), rather than the 3mg most pills come in. A teaspoon of raw honey before bed helps prevent some people from waking multiple times throughout the night.

Consider reading this excellent info from Yvain on sleep apnea, especially if you snore excessively or feel very tired even after a full night's sleep.

Cancer

Almost all of the risk factors for cancer have some overlap with CVD, meaning most of the advice above works for cancer too, but there are a few additional considerations worth discussing.

Cancer and UV exposure

One of the surprising results of my research was that conventional wisdom appears to be wrong here. There is not a simple relationship between UV exposure and increased cancers. Specifically, while increased sunlight exposure is correlated with higher incidence of skin cancer, it appears that it is also correlated with a decreased risk of 5 other cancers that are far less survivable.^[1] This is a straightforward trade off, getting sun exposure wins by quite a lot. Shade your face to avoid photodamage to your skin and macular degeneration of your eyes.

Breast cancer and testicular cancer

Redacted, see Vaniver's comment here.

Floss

No, seriously. Not flossing is way more lethal than you think.^[1] You should also see a dentist regularly, even if you have to pay for your own insurance. (It's surprisingly cheap, e.g. Delta Dental offers plans for under $100/yr; lots of people don't make use of their plan and subsidize the treatment of those who do use theirs). Losing teeth greatly increases your chances of infections over time.

Things that will kill you right now

Avoidable medical errors

Avoidable medical errors might be the second leading cause of death after CVD.^[1] This makes a hospital visit possibly the most dangerous thing you can do, especially if you are young. In general, you should not assume that medical staff are competent. Triple check dangerous prescriptions. If you don’t know whether a prescription is dangerous, assume it is. Ask medical staff if they’ve washed their hands (yes, this is actually still a major problem). Sharpie on yourself which side of your body a surgery is supposed to happen on, along with your name and what the surgery is for (seriously). Keep your own records, especially if you have serious medical issues; error rates in medical documentation are ridiculous. Medical equipment is generally cleaned by custodial staff with no medical training who often don't know how a particular device works. Have someone you can call in an emergency who knows about all of this.

While we're discussing medicine, I'll throw in a couple low cost recommendations that give me peace of mind, even if an emergency situation is unlikely. The first is that the Red Cross has created an android/iphone app covering first aid with extensive pictures and videos helping you through the situation. The second is quickclot which can stop severe bleeding much faster than traditional techniques.

Unintentional poisoning

This is mostly acetaminophen poisoning resulting from their mandatory inclusion in pain killers to prevent abuse. Also people misdosing themselves with legal and illegal drugs. Be careful, this outweighs traffic accidents in accidental deaths. Adding the 24 hour emergency poison control line number (1-800-222-1222) to your phone is something you can do right now. It is also worth knowing that SOP for acetaminophen poisoning is high dose NAC, which is freely available on amazon in the US (h/t Tara).

Traffic accidents

Michael Curzi has a great post on this I won’t attempt to reproduce here: How to avoid dying in a car crash. It is definitely worth updating your model of what behaviors are dangerous in a car.

Summary of interventions

1. If you know people who smoke, getting them to vape is the single largest impact you can have on their lifespan.

2. Pay attention when in your car.

3. CONSTANT VIGILANCE when dealing with the medical profession and drugs.

4. Exercise: very high return on first few units of effort, some cardio and some resistance training is best.

5. Blood donation every 12-24 months for men.

6. Buy a blood pressure monitor and do blood pressure reduction interventions if needed.

7. Eat fish, nuts, eggs, fruit, dark chocolate. Supplement Vitamin D3.

8. Work towards a healthy weight.

9. If you are losing sleep/are stressed, try one small intervention at a time, and don’t get discouraged.  These interventions are the hardest but potentially the most rewarding. Supplements for stress, anxiety, and sleep are somewhat subjective and vary more in reported efficacy than others; self-experimentation is recommended.

10. Floss (and see a dentist).

Closing

Don’t worry too much. Don’t get down on yourself about health.  This creates an ugh field making you less likely to take action.  The process of becoming healthier is going to make you feel stupid sometimes. This is a marathon and not a sprint; standard habit forming rules apply. Trying to fix 10 things at once is highly stressful! Do not do this! Discuss things that worked for you and didn’t work for you in the past with yourself and with others and come up with a plan. Don’t publicly commit to your plan in the comments, this makes you less likely to do it. Oh, and feel free to argue with me or request more sources.