 According to the largest study of risk factors for death in human history, a poor diet causes more death than anything. Cigarettes only kill about 8 million people a year, whereas humanity's diet kills millions more. What's the worst aspect of our diet? Processed meat, a Twinkie, soda? No. The five deadliest things about our diet are inadequate fruit intake, not enough fruit, not enough whole grains, not enough vegetables, too much salt, and not enough nuts and seeds. Nuts should come as no surprise, since interventional trials have shown that eating nuts improves artery function and arterial diseases like heart disease are among our leading killers. But that's not all nuts can do. They may also improve blood sugar control, lower cholesterol, suppress inflammation, reduce oxidative stress, and feed our friendly gut flora. All nuts are just tree nuts. What about peanuts? What about peanut butter? About 50% of peanut consumption in the U.S. is through peanut butter, but the association between peanut butter and mortality has not been thoroughly evaluated. To get that granular, though, we can call on the NIH AARP study. It's the largest prospective health and diet study in history that followed more than a half million people since the 1990s. And nut consumption in general appeared to protect against all-cause mortality, meaning nut eaters live on average longer lives, and specifically are less likely to die from cancer, cardiovascular disease, respiratory disease, infectious causes, so maybe they help immunity as well, liver disease, and kidney disease. However, no such associations were found for peanut butter. So when it comes to living longer, peanut butter doesn't seem to count. Why? Well, we know peanut butter consumers tend to eat more meat, smoke cigarettes, and we're less likely to exercise, but the researchers controlled for all that— red meat, white meat, tobacco use, exercise, and vegetables, fruits, and whole grains, so it's not like the peanut butter eaters were just eating more white bread sandwiches or something. The researchers didn't control for sugar, though, so it's possible they could have been eating more sugary jelly. It could also be the processing that goes into making peanut butter, the added trans fat, oil, salt, and sugar, but regular nuts are also often needed with added oil, sugar, and salt. Could it just be the peanuts themselves? I mean, technically they aren't nuts, so maybe they just don't have the same benefits, but no, a meta-analysis of all such studies found the same nut-like benefits for whole peanuts, just not peanut butter. Well, one thing missing from even no salt, oil-free, sugar-free, nut-and-seed butters is intact cellular structure. As I noted, and how not to diet, no matter how well we chew, whole or chopped nuts, some of the nutrients remain trapped in tiny particles that deliver a bounty of prebiotic goodness to our friendly flora. That makes me wonder if there would have been any difference between chunky and smooth peanut butter. In the meanwhile, there is compelling evidence to recommend the use of nuts, preferably raw nuts over salted or toasted, and whole or chopped nuts rather than nut butters, at least three times a week in order to maximize our chances of living longer and healthier lives.