One Heartbeat per Second to Beat the Clock

Immanuel Kant, the famed 18th century philosopher, described the chemistry of his day as a science, but not really science, as it wasn’t grounded in mathematics—at least not until a century later. The same could be said for biology, the study of life.

In math, physics, and quantum physics, there are constants: physical quantities thought to be both universal and unchanging. Biology, though, was considered too complex and too messy to be governed by simple, natural laws. In 1997, however, a theoretical high-energy physicist from Los Alamos joined two biologists to describe universal scaling laws that appear to apply across the board. Are there any clinical implications of these types of theories?

A fascinating observation was published. As I discuss in my video Finger on the Pulse of Longevity, the number of heartbeats per lifetime is remarkably similar whether you’re a hamster all the way up to a whale. So, mice, who typically live less than two years, have a heart rate of about 500 to 600 beats a minute—up to 10 beats a second. In contrast, the heart of a Galapagos tortoise beats 100 times slower, but they live about 100 times longer. There’s such a remarkable consistency in the number of heartbeats animals get in their lifetimes that a provocative question was asked: “Can human life be extended by cardiac slowing?” In other words, if humans are predetermined to have about three billion heartbeats in a lifetime, then would a reduction in average heart rate extend life? This is not just some academic question. If that’s how it works, then one might estimate that a reduction in heart rate from an average of more than 70 beats per minute down to what many athletes have, 60 beats per minute, could theoretically increase life span by more than a decade.

This reasoning may seem a bit off the wall, but that’s how the scientific method works: We start out with an observation, such as this striking heartbeat data, and then make an educated guess (or hypothesis) that is then put to the test. How might one demonstrate “a life-prolonging effect of cardiac slowing in humans”? Perhaps a first attempt would be to see if people with slower heart rates live longer lives. Unfortunately, researchers couldn’t just give subjects drugs that only lower heart rate. Drugs like beta blockers at the time lowered both heart rate and blood pressure, so they weren’t ideal for testing the question at hand. We can, however, do that first part and look at whether people with slower heart rates live longer.

“From the evidence accumulated so far, we know that a high resting heart rate,” meaning how fast our heart beats when we’re just sitting at rest, “is associated with an increase in…mortality in the general population,” as well as in those with chronic disease. A faster heart rate may lead to a faster death rate. Indeed, faster resting heart rates are associated with shorter life expectancies and are considered a strong independent risk factor for heart disease and heart failure. Researchers found that those with higher heart rates were about twice as likely over the next 15 years to experience heart failure. This was seen in middle-aged people, as well as observed in older people. It was also found in men and women. What’s critical is that this link between how fast our heart goes and how fast our life goes is independent of physical activity.

At first, I thought this was painfully obvious. Of course lower resting heart rates are associated with a longer lifespan. Who has a really slow pulse? Athletes. The more physically fit we are, the lower our resting pulse. But, no: Researchers “found that irrespective of level of physical fitness subjects with higher resting heart rates fare worse than people with lower heart rates,” so it appears a high resting heart rate is not just a marker of risk, but a bona-fide risk factor independent of how fit we are or how much we exercise.

Why? If our heart rate is up 24 hours a day, even when we’re sleeping, all that pulsatile stress may break some of the elastic fibers within the arterial wall, causing our arteries to become stiff. It doesn’t allow enough time for our arteries to relax between beats, so the faster our heart, the stiffer our arteries. There are all sorts of theories about how an increased resting heart rate can decrease our time on Earth. Regardless, this relationship is now well recognized.

It is not just a marker of an underlying pathology nor can it be said to be merely a marker of inflammation. The reason it’s important to distinguish a risk factor from a risk marker is that if you control the risk factor, you control the risk. But, if it were just a risk marker, it wouldn’t matter if we brought down our heart rate. We now have evidence from drug trials—indeed, there are now medications that just affect heart rate—that lowering our heart rate lowers our death rate.

It’s been shown in at least a dozen trials so far. Basically, we don’t want our heart to be beating more than about one beat per second at rest. (Measure your pulse right now!) For the maximum lifespan, the target is about one beat a second to beat the clock. Don’t worry if your heart’s beating too fast: Heart rate is a modifiable risk factor. Yes, there are drugs, but there are also lifestyle regimens, like eating beans, that can bring down our resting pulse. See Slow Your Beating Heart: Beans vs. Exercise.


Other lifespan-expanding strategies are detailed in:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Reversing Diabetic Blindness with Diet

Though many reported feeling better on Dr. Walter Kempner’s rice and fruit diet, he refused to accept such anecdotal evidence as proof of success. He wanted objective measurements. The most famous were his “eyegrounds photographs,” taken with a special camera that allowed one to visualize the back of the eye. In doing so, he proved diet can arrest the bleeding, oozing, and swelling you see in the back of the eye in people with severe kidney, hypertensive, or heart disease. Even more than that, he proved that diet could actually reverse it, something never thought possible.

In my video, Can Diabetic Retinopathy Be Reversed?, you can see before and after images of the back of patients’ eyes. He found reversal to such a degree that even those who could no longer distinguish large objects were able to once again read fine print. Dr. Kempner had shown a reversal of blindness with diet.

The results were so dramatic that the head of the department of ophthalmology at Duke, where Kempner worked, was questioned as to whether they were somehow faked. He assured them they were not. In fact, he wrote in one person’s chart, “This patient’s eyegrounds are improved to an unbelievable degree.” Not only had he never seen anything like it, he couldn’t remember ever seeing a patient with such advanced disease even being alive 15 months later.

The magnitude of the improvements Kempner got—reversal of end-stage heart and kidney failure—was surprising, simply beyond belief. But as Kempner said as his closing sentence of a presentation before the American College of Physicians, “The important result is not that the change in the course of the disease has been achieved by the rice diet but that the course of the disease can be changed.”

Now that we have high blood pressure drugs, we see less hypertensive retinopathy, but we still see a lot of diabetic retinopathy, now the leading cause of blindness in American adults. Even with intensive diabetes treatment—at least three insulin injections a day with the best modern technology has to offer—the best we can offer is usually just a slowing of the progression of the disease.

So, in the 21st century, we slow down your blindness. Yet a half century ago, Kempner proved we could reverse it. Kempner started out using his plant-based rice diet ultra-low in sodium, fat, cholesterol, and protein to reverse kidney and heart failure; he actually assumed the diet would make diabetes worse. He expected a 90% carbohydrate diet would increase insulin requirements, however, the opposite proved to be true. He took the next 100 patients with diabetes who walked through his door who went on the rice diet for at least three months and found their fasting blood sugars dropped despite a drop in the insulin they were taking. What really blew people away was this: Forty-four of the patients had diabetic retinopathy, and, in 30% of the cases, their eyes improved. That’s not supposed to happen; diabetic retinopathy had been considered “a sign of irreversible destruction.” What does this change mean in real life? Patients went from unable to even read headlines to normal vision.

The remarkable success Dr. Kempner had reversing some of the most dreaded complications of diabetes with his rice and fruit diet was not because of weight loss. The improvements occurred even in those patients who did not lose significant weight, so it must have been something specific about the diet. Maybe it was his total elimination of animal protein, animal fat, and cholesterol? Or perhaps it was his radical reduction in sodium, fat, and protein in general? We don’t know.

How do we treat diabetic retinopathy these days? With steroids and other drugs injected straight into the eyeball. If that doesn’t work, there’s always pan-retinal laser photocoagulation, in which laser burns are etched over nearly the entire retina. Surgeons literally burn out the back of your eye. Why would they do that? The theory is that by killing off most of the retina, the little pieces you leave behind may get more blood flow.

When I see that, along with Kempner’s work, I can’t help but feel like history has been reversed. It seems as though it should have gone like, “Can you believe 50 years ago the best we had was this barbaric, burn-out-your-socket surgery? Thank goodness we’ve since learned that through dietary means alone, we can reverse the blindness.” But instead of learning, medicine seems to have forgotten.

I documented the extraordinary Kempner story previously in Kempner Rice Diet: Whipping Us Into Shape and Drugs and the Demise of the Rice Diet. The reason I keep coming back to this is not to suggest people should go on such a diet (it is too extreme and potentially dangerous to do without strict medical supervision), but to show the power of dietary change to yield tremendous healing effects.

The best way to prevent diabetic blindness is to prevent or reverse diabetes in the first place. See, for example:

Why wouldn’t a diet of white rice make diabetes worse? See If White Rice Is Linked to Diabetes, What About China?

For more on the nitty gritty on what is the actual cause of type 2 diabetes, see:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: