How Not to Diet

by Michael Greger

Healthier habits just need to become a way of life. That means the new eating pattern has to be one you can stick with and also, ideally, be health-promoting overall. If it’s going to be lifelong, you want it to lead to a long life. Is it too much to ask for one diet to be effective, sustainable, and life-extending?

As we’ve discussed, completely avoiding some problem foods may paradoxically sometimes be even easier than attempting to moderate their intakes.2517 This is readily apparent in the substance-use literature, where entirely avoiding alcohol is more effective and, ironically, easier for a problem drinker than just cutting down.2518

So rather than “All things in moderation,” a better aphorism may be “Big changes beget big results.”2522 That old adage “Shoot for the moon—if you fail, you will land among the stars” was obviously written by someone without even the vaguest understanding of astronomy, but the reverse does make decent dietary sense. So shoot for the stars!

Success breeds success. After a few weeks of eating more healthfully, you may feel so much healthier that your resolve is reinforced.

Obviously, with very-low-calorie starvation diets, you can drop people down to any weight, but quick fixes tend to quickly unravel,2528 whereas the whole point of whole food, plant-based nutrition is to maximize long-term health and longevity. I mean, even if, for example, low-carb, ketogenic diets were found to be as effective (and they don’t appear to be),2529 the point of weight loss is not to fit into a skinnier casket.

Beyond just the increased rates of constipation, headache, bad breath, muscle cramps, general weakness, and rash reported on low-carbohydrate diets,2530 people whose diets simply tend to sway that way appear to live significantly shorter lives.

On the other hand, eating plant-based2532 or even just trending in the direction of eating more healthy plant foods is associated with increased likelihood of living longer.2533 Those who start out more plant-based but then add meat to their diets at least once a week not only appear to double or triple their odds of diabetes, stroke, heart diseases, and weight gain but suffer an associated 3.6-year drop in life expectancy.2534

whole food, plant-based diets have been shown to actually reverse heart disease.2537

Isn’t it all a bit too convenient? The same foods that check off the most ideal weight-loss ingredients are the same foods that rack up the most points on health and longevity? And whole plant foods aren’t just heart-healthy, but brain-, kidney-, and liver-healthy too. What are the odds?

So for the first 90 percent of our hominoid existence, our bodies evolved on mostly plants.2540

We’ve known for more than a century that you can clog the arteries of herbivores like rabbits by feeding them meat, eggs, and dairy,2541 but it’s virtually impossible to induce atherosclerosis in a carnivore with cholesterol because that’s part of their natural diets.2542

rats eating rat food don’t get fat, but give them Oreos and it’s a different story. Perhaps it’s no wonder that our bodies may thrive best on the diet we were designed to eat. So may...

Self-monitoring has been shown to be an effective behavioral technique for helping people eat more healthfully, exercise more,2570 and drink less alcohol,2571 but unlike in those cases, self-weighing is monitoring an outcome rather than specific behaviors.

self-weighing among overweight and obese adults appears to actually improve psychological health and well-being.

Among those adults needing to lose weight, self-weighing seems to be associated with less depression, less disordered eating, and less body dissatisfaction, but this may be confounded by the fact that regular self-weighing improves weight loss.2583

Alcohol is another plant product that shouldn’t be used during pregnancy and activates AMPK, but by a totally different mechanism. Alcohol is detoxified in the body into acetic acid, which our bodies have to use ATP to metabolize.

AMPK is therefore activated naturally in response to the energy expenditure.2632 The problem is that before alcohol gets fully converted into acetic acid, there’s a toxic intermediate called acetaldehyde, which is a known carcinogen.

That may be why alcohol consumption is understood to increase the risk of at least a half dozen different cancers,2633 including breast cancer, even among light drinkers.2634

In a study refreshingly not funded by a vinegar company, two daily tablespoons of apple cider vinegar mixed into a drink reduced fasting blood sugars in prediabetics an average of sixteen points within one week, which is better than what you’d tend to see with antidiabetic drugs like Glucophage or Avandia.

The mystery was solved when a research team in Greece demonstrated that vinegar consumption improves the uptake of blood sugar by our muscles,2655 an AMPK effect also seen with exercise.2656

There are some important caveats when it comes to vinegar, though. First, never drink it straight. It can cause intractable hiccups2662 and burn your esophagus,2663 as can apple cider vinegar tablets if they get lodged in your throat.

until we know more, I’d recommend sticking with more common culinary-type doses, like two tablespoons a day, which is considered safe.2667 Acetic acid is metabolized quickly in the body,2668 so I’d recommend splitting up the daily dose to activate AMPK throughout the day, rather than taking it all at once.

Given the additional mealtime benefits on blood sugars, insulin, and satiety, I’d recommend taking it with food. In the clinical trials, the belly fat–burning dose was two tablespoons a day. Splitting that over three meals would be two teaspoons a meal.

To amp AMPK, I recommend trying two teaspoons of vinegar with each meal. You might be thinking, Wait—vinegar for breakfast? Those aghast at the thought of drizzling vinegar on their oatmeal may have never heard of chocolate vinegar, strawberry vinegar, or any of the dozens of other exotic flavors out there.

There are savory varieties like hickory smoke, garlic, and herb vinegars for main dishes and sweet selections like apricot and blackberry ginger—and those are just the ones I happen to have in my kitchen right now!

You can also incorporate vinegar into your meals by always having a side salad or even adding it to tea with some lemon juice. For a bonus, you can slice some bell peppers and sprinkle some barberries on your salad, and, if you sweeten your tea with honey or sugar, try yacon syrup instead.

Two teaspoons of chia seeds, which have around thirty-five calories, seemed to work as well as three teaspoons. The yogurt-and-chia subjects, however, ended up eating nearly three hundred fewer calories at lunch, so in effect, the chia could be thought as having “negative” calories. We don’t know if the subjects somehow compensated later on by eating more at dinner, but if adding chia to your diet means eating hundreds fewer calories day after day due to their satiating effects, you’d expect to lose weight over time. You don’t know, though, until you put it to the test.

For example, one study found that menopausal women randomized to a gram a day (less than a quarter teaspoon) of black cumin powder reduced their bad LDL cholesterol by 27 percent within two months.2734 That’s the kind of result you’d expect taking a statin drug, but it was achieved with just a sprinkle of a spice. Black cumin may also help with menopausal symptoms themselves.2735

Now, taking black cumin didn’t cure anything—a month after stopping the spice, cholesterol levels crept back up2736—but it does appear to be a cheap, safe, effective, and tasty (if you like spice) treatment for some of our deadliest risk factors. And the side effects? Loss of appetite and weight loss.2737 Bingo!

A recent systematic review and meta-analysis of randomized, controlled weight-loss trials found that about a quarter teaspoon of black cumin powder every day appears to reduce bod...

Not only did those who ate the oatmeal feel significantly fuller and less hungry, some then went on to consume significantly less at lunch. Overweight participants who had eaten oatmeal for breakfast consumed less than half as many calories at lunch, about four hundred fewer calories, which is more than the oatmeal itself had contained.2765 So in effect, the oatmeal provided “negative” calories.

Slave to the Rhythm

For billions of years, life on Earth evolved to the twenty-four-hour cycle of light and dark, so it’s no surprise our bodies are finely tuned to that pattern. When people are in total darkness without any external time cues, our bodies still continue to cycle in about a twenty-four-hour circadian rhythm.2800

At night while we’re sleeping, a whole array of internal housekeeping activities can be switched on, such as clearing accumulated waste products from the brain, for example, and as dawn approaches, our bodies can shift back into activity mode.

properly timed chemotherapy can not only end up being five times less toxic but twice as effective against cancer.2808 The same drugs, at the same doses, but with different effects depending on the time they’re given. Our bodies absorb, distribute, metabolize, and detoxify what we ingest differently depending on when the processes are occurring during the twenty-four-hour cycle.

If chronotherapy—the optimal timing of drugs—can have such an impact, it may come as no surprise that chronoprevention—the scheduling of lifestyle interventions like mealtimes—can also make a difference.

In addition to slimming nearly an extra two inches off their waistlines, by the end of the twelve-week study, the king-prince-pauper group lost nineteen pounds compared to only eight lost by the pauper-prince-king group despite eating the same number of calories.2830 Eleven additional pounds lost eating the same number of calories. That’s the power of chronobiology.

700/500/200 is 50 percent of calories at breakfast, 36 percent of calories at lunch, and only 14 percent at dinner. What about 20 percent of calories for dinner? How would a calorie percentage spread of 50/30/20 compare to eating 20 percent of calories at breakfast, 30 percent at lunch, and 50 percent at dinner? Again, the bigger-breakfast group experienced “dramatically increased” weight loss, about nine pounds difference in just eight weeks with no significant difference in overall caloric intake or physical activity between the groups.2831

researchers concluded that one clear communication physicians could give is: “If you want to lose weight, eat more in the morning than in the evening.”2832

Simply telling people to eat their main meal at lunch rather than dinner may help. Despite comparable caloric intakes, participants in a weight-loss program randomized to get advice to make their main meal lunch beat out those who were instead told to make dinner their primary meal.2833

Why do calories eaten in the morning seem to be less fattening than calories eaten in the evening? One reason is that more calories are burned off in the morning due to diet-induced thermogenesis, the amount of energy the body takes to digest and process a meal, given off in part as waste heat.

When people are given the exact same meal in the morning, afternoon, and at night, their body uses up about 25 percent more calories to process the meal in the afternoon than at night and about 50 percent more calories to digest it in the morning.

Regardless of activity level or sleeping cycle, the calories burned while processing the morning meals were 50 percent higher than the evening meals.2838 So the difference is explained by chronobiology; it’s just part of our circadian rhythms to burn more meal calories in the morning.

How does it make sense for our bodies to race through calories in the morning when we have the whole day ahead of us? Perhaps our bodies aren’t so much wasting calories as investing them. When we eat in the morning, our bodies bulk up our muscles with glycogen, which is the primary energy reserve we use to fuel our muscles. That takes energy, though.

In the evening, our bodies expect to be sleeping for much of the next twelve hours, so rather than storing blood sugar as extra glycogen in our muscles, the body preferentially uses it as an energy source,...

In the morning, however, our bodies expect to be running around all day, so instead of just burning off breakfast, our bodies continue to dip into our fat stores while we use breakfast calories to stuff our muscles full of the energy reserves we need to move around over the course of the day.

So consuming more calories in the morning relative to the evening may actually have the triple benefit of more weight loss, better blood sugar control, and lower heart disease risk.

The way we know these cycles are driven by local clocks rather than being controlled by our brains is that we can take surgical biopsies of fat, put them in a petri dish, and still observe their natural rhythm.

several lines of evidence now implicate chronodisruption—the state in which our central and peripheral clocks diverge out of sync—as playing a role in conditions ranging from premature aging and cancer2877 to mood disorders and obesity.2878

Just as avoiding bright light at night can prevent circadian misalignment, so can avoiding eating at night. We may have no control over the lighting at our workplaces, but we can try to minimize overnight food intake,