Living to 100 is boring. Walking up stairs at 80 is the actual goal.

The average American lives to about 77. The average American spends the last 12 years of that life with at least one chronic disease that significantly affects daily function. That is not a long life with a clean ending. That is a medium length life with a long, slow, expensive, exhausting decline at the end of it.

The goal of any serious longevity practice is not to add a few years onto that decline. The goal is to compress the decline. To live well until 80, and then to die over a relatively short period instead of a long one. This is sometimes called squaring the curve. The wellness industry rarely talks about it this way because it is less exciting than promising you a hundred and twenty years. It is, however, the only goal that is actually on offer.

Peter Attia has built a large part of his career making this distinction clear, and his book Outlive is the most useful single source I have read on the topic. The framework he uses, and that I find genuinely helpful, is to imagine the version of you that you want to be at 85, write down what you want them to be able to do, and reverse engineer what your 45 or 55 year old self needs to be doing today to make that possible.

If you remove accidents from the equation, the overwhelming majority of people in developed countries die from one of four categories of disease. Cardiovascular disease. Cancer. Neurodegenerative disease, primarily dementia. And metabolic disease, which is largely Type 2 diabetes and its complications. These are sometimes called the four horsemen of medicine.

Here is the deeply important thing that wellness marketing almost never mentions. The risk factors for these four diseases overlap massively. The same handful of behaviors influence all of them. Cardiovascular fitness reduces risk of cardiovascular disease, several cancers, dementia, and Type 2 diabetes. Muscle mass and strength reduce risk across all four. Sleep quality affects all four. Metabolic health, particularly insulin sensitivity, affects all four. Diet quality affects all four.

This is wonderful news, because it means you do not need a different intervention for each disease. You need the small set of behaviors that move the dial on all of them, done consistently, over decades. The compound interest of small behaviors is the entire longevity game. There is no magic pill, and the people selling you one are either lying or selling you something that, at best, marginally tweaks a curve that your daily life is determining.

If I could measure one thing about your future health, I would measure your VO2 max, the maximum volume of oxygen your body can use per minute. It is the gold standard measure of cardiorespiratory fitness, and the relationship between VO2 max and all cause mortality is one of the strongest in all of medicine.

A 2018 study in JAMA Network Open, following more than 122,000 patients over years of follow up, found that low cardiorespiratory fitness was associated with risk of death greater than the risk associated with smoking, diabetes, and hypertension combined. Read that twice. The most fit quintile had a roughly five fold lower mortality risk than the least fit. There is no drug that does this. There is no supplement that does this. There is no surgery that does this. Cardio does this.

The good news is that VO2 max responds to training at every age studied. You build it with zone 2 cardio, the boring kind where you can hold a conversation but it would be slightly annoying, done for 150 to 200 minutes a week. You sharpen it with shorter, harder intervals once a week, four minutes near your maximum, repeated four times with rest between. This is called the Norwegian 4x4 protocol and it has more peer reviewed support than almost anything else in fitness science.

If you do nothing else for your future health, do this. Walk fast, hike hills, cycle, swim, jog, row. 150 minutes a week. The single most powerful drug, available at your local park, completely free.

I wrote a whole essay about this in the Movement room and I will not repeat it all here, but it deserves its place in any honest longevity framework. The strongest predictor of late life independence is muscle mass and grip strength. Both are highly trainable. Both atrophy quickly when ignored. Both are extremely cheap to maintain compared to the cost of losing them.

Grip strength specifically is one of the single best biomarkers of biological aging we have. Studies tracking grip strength across decades show it predicts cardiovascular disease, fracture risk, cognitive decline, and all cause mortality. Carrying heavy things is not a vanity activity. It is medicine.

Two strength sessions a week, hitting all the major movement patterns, is the floor. Three is the sweet spot. Anything in that range, sustained over decades, dramatically lowers the probability that you will spend your final years dependent on other people to help you out of a chair.

Insulin resistance is the slow burning fire underneath most chronic disease. It is the metabolic state where your cells stop responding properly to insulin, your pancreas pumps out more and more of it to compensate, and your blood sugar slowly creeps up over years and decades. By the time it shows up as Type 2 diabetes on a standard blood test, the damage has often been accumulating for a decade or more.

The good news is that insulin resistance is one of the most reversible conditions in modern medicine, and the levers are exactly the ones already mentioned. Cardio. Strength. Sleep. Protein and fiber forward eating. Avoiding the constant grazing pattern of modern life. None of this is exotic. All of it works.

If you want one cheap, useful blood marker to track over time, ask your doctor for fasting insulin alongside fasting glucose. The combination, fed into something called the HOMA IR calculation, gives you a reasonable early window into your metabolic trajectory years before standard markers go bad. Most doctors will not order it unless you ask. So ask.

I will spare you a fifteen page review of the supplement aisle. Here is the short version, with the honest caveat that this is a fast moving field and any specific recommendation may look dated in two years. The evidence is reasonably solid for a small number of things in most adults. Creatine monohydrate, 5 grams a day, for muscle, brain, and bone. Vitamin D in deficient populations. Omega 3s, ideally from fatty fish a few times a week or from a third party tested algae or fish oil. Magnesium glycinate for sleep and muscle. A protein supplement only if you cannot hit protein targets from food.

Almost everything else, including the trendy longevity drugs you have read about, is in the category of interesting science with thin or zero human evidence for the goals you actually care about. NAD precursors, rapamycin, metformin in non diabetics. They are not nothing, but they are also not the difference between a good 80 and a bad 80. Your behaviors are.

If you want to spend money on longevity, spend it on a gym membership, real food, blackout curtains, a good mattress, and an annual checkup that includes the right blood work. Then put the rest in an index fund. Future you, the one with intact knees and an unbroken mind, will thank you.