How Not to Diet utilizes Dr. Greger’s years of experience and thousands of studies to encourage you to move away from fad diets and towards evidence-based diet practices. Our diets are paramount to our overall health. Still, we often gravitate towards the end result instead of the process itself. This approach can have harmful effects. Many diets are incredibly unhealthy. When choosing something as life-or-death as what you put in your mouth, we need the most accurate evidence possible. Backed up by almost 5,000 references, How Not to Diet offers a diet that’s both sustainable and healthful.
About Dr. Michael Greger
Dr. Michael Greger is a physician, New York Times bestselling author, and internationally recognized speaker on nutrition, food safety, and public health issues. A founding member and Fellow of the American College of Lifestyle Medicine, Dr. Greger is licensed as a general practitioner specializing in clinical nutrition. He is a graduate of the Cornell University School of Agriculture and Tufts University School of Medicine. In 2017, Dr. Greger was honored with the ACLM Lifestyle Medicine Trailblazer Award and became a diplomat of the American Board of Lifestyle Medicine. 100% of all proceeds he has ever received from his books, DVDs, and speaking engagements always have and will always be donated to charity.
Obesity is a greater epidemic than it has ever been. Greger explains we are currently ten times fatter than we were 100 years ago. Additionally, this growth in obesity has not been linear. Instead, obesity in developed nations has grown exponentially in the last fifty years. Worryingly, this increase in obesity is showing no signs of slowing down. Some diets claim the issue is your willpower. Greger challenges this claim and instead explains our bodies simply react to the food we eat in the way it has been designed.
The human body evolved within environments where food was scarce. Due to this scarcity, we have evolved to store excess calories as fat to survive the winter months. Additionally, we tend to crave high-calorie foods more for this same reason. The reason for the obesity epidemic is that these high-calorie foods are now readily available. The 70s brought with it deep-freezing and ready meals. Plus, an introduction of treat foods as an everyday option. The issue with the increased processing characterized by the 80s is these food items lack fiber and nutritional value. Plus, they are filled with added sugars and oils. Greger calls these foods CRAP (calorie-rich and processed).
Ingredients for the Ideal Weight Loss Diet
High in Fiber-Rich Foods
As explained, one of the greatest issues associated with CRAP foods is they lack fiber. Greger believes eating fiber-rich foods is integral to losing weight. Firstly, fiber is satiating while also containing few calories. Additionally, as fiber-rich foods often take longer to chew and eat, you will also get full faster. Essentially, fiber-rich foods allow you to get full quickly and for a more extended period without a significant number of calories. Greger offers an example of apples and apple juice to explain the importance of fiber. On average, one glass of apple juice will contain five apples. The former can be drunk in a matter of seconds and will not keep you full for very long. Comparatively, the latter will take you considerably longer to eat and will also keep you full for longer. The difference between these two is the presence of fiber.
Another benefit of fiber-rich foods is that they can trap the calories in food. Due to plant fibers having a tough outer layer, your colon will take longer to digest this food. Subsequently, your colon will not extract all the calories. Therefore, despite obtaining enough energy, you are less likely to store plant fiber as fat.
Finally, fiber-rich foods nourish our gut microbiome. Gut bacteria thrive on fiber and subsequently release short-chain fatty acids that reduce our appetite and boost our metabolism. For example, Greger explains that a 2017 study found that CRAP foods, like donuts, are far less appetizing after eating a fiber-rich meal. This effect lasts even up to 12 hours after a meal.
We must do much better on the fiber-front. Less than 5% of Americans meet the minimum daily fiber recommendations. Therefore, to increase the amount of fiber in your diet, introduce more root vegetables, and legumes to your weekly shop.
Low Glycemic Load
“To remove refined grains from your diet is to remove America’s number one source of calories. Switching to whole grains may help reduce body fat, but there’s an even better swap. See the Wall Off Your Calories section for taking your grain game up a notch and graduate from mere whole grains to intact whole grains, such as oat groats (also known as hull-less or hulled oats).” – Dr. Michael Greger
A common argument made by low carb diets is that you should aim for foods with a low glycemic load. This is one feature of diet fads that is correct, even though Dr. Greger does not advocate for low carb diets. Instead, Greger suggests you avoid foods that can cause blood sugar spikes, like white bread. White bread tastes sweet after you eat it because your body can digest this type of bread so quickly. Having high glycemic index foods in your diet will only lead to cravings. On the flip side, replacing with high glycemic index foods will provide you with a slow release of energy that prevents overeating.
Another benefit of introducing more high glycemic index foods is you will no longer struggle with weight loss plateaus. Individuals who cut all carbs out of their diet are at risk of lowering their metabolism. Subsequently, they initially lose some weight and then their weight loss plateaus. However, continuing to eat carbs, but ones with a high glycemic index, will allow you to continue losing weight. Hence, Greger recommends swapping white rice, bread, and cereals for whole grains, legumes, and oats.
Low in Added Sugar, Fat, and Meat
“It’s been argued that for about 99.8 percent of our time on Earth, it was virtually impossible for us to regularly consume more than 15 percent of calories as fat.” – Dr. Michael Greger
Fat has a greater calorie per gram rate than sugar. Greger agrees that added sugars should be eliminated from your diet; however, he also believes unhealthy fats are driving the obesity epidemic. Intuitively, fat is far easier for our bodies to convert into body fat than sugar. Plus, we are obtaining a far larger proportion of our calories from fat than we used to. Animal agriculture is partly to blame, as animals are bred to be far fatter than they used to be. Therefore, you need to cut out all dairy, oils, and meat. To support this point, Greger points towards a study by Dr. Dean Ornish. Ornish found that by living on a whole food plant-based diet participants lost an average of 24 pounds.
As well as cutting out animal products, which are the primary sources of fat, Greger also recommends cutting out added sugar. We now eat twelve times more sugar than we did 200 years ago. Crucially, sugar has zero nutritional value and simply offers excess calories. In fact, studies have shown that children given high-sugar cereals ate 7% more than children who had a low-sugar alternative. Therefore, eating excess sugar will only make you eat more. You might initially struggle to cut out animal products and sugar. However, your tastebuds will quickly adapt, and you will no longer notice the difference.
Low in Calorie Density
Your typical meal should be filled with foods that have a low-calorie density. Greger explains that one of the greatest benefits of adopting a whole food plant-based diet is you do not have to restrict your portions. You can eat unlimited quantities of food and still lose weight. Foods that have a low-calorie density generally have high water content. Examples of these foods are non-starchy vegetables and fruits. Generally, we eat the same amount of food each day, determined by stretch receptors in our stomach. Therefore, if we fill our diet with low-calorie density foods, we will easily lose weight. Plus, you can eat as many courgettes, apples, pears, and other nutritious foods as you like.
Rich in Legumes
“Legumes have been found to be perhaps “the most important dietary predictor of survival in older people” around the world.” – Dr. Michael Greger
Greger describes legumes as a wonder food. He explains that Hispanic Americans are an anomaly in America. They have a lower risk of cancer and heart disease despite typically being in the lower economic range. The most popular theory to explain this trend is that they have a legume-rich diet. Greger describes a legume as falling somewhere between a vegetable and a protein. It is filled with several essential nutrients, such as iron, zinc, potassium, and fiber. However, they are also rich in protein. The high fiber content of legumes makes them essential to weight loss. Greger provides several examples of studies where legume eaters were compared directly with individuals eating animal products. In each of these studies, the legume eaters ate fewer calories at their next meals. They also reported being less hungry later in the day. Legumes are inexpensive and can be bought ready-cooked in a tin.
A feature of diet fads, like weight watchers, is the idea of accountability. Greger believes this is one of the strengths of these diet fads, even if they get the rest of the details completely wrong. Try to establish a support network of communities that can offer you a support structure and accountability. Research suggests that having these structures in place as you start a diet will significantly improve your chances of success. If you struggle to find a whole food plant-based group locally or online, then you should always stay accountable to yourself. For example, Greger highlights a study where participants who weighed themselves once a week consistently lost weight. However, Greger recommends you take this one step further and weigh yourself twice a day.
Drink Lots of Water
“Drinking two cups of water increased the metabolic rate of men and women by 30 percent. The increase started within ten minutes of water drinking and reached a maximum within an hour. In the ninety minutes after drinking a single tall glass of water, the subjects burned an extra twenty-four calories. Simply drinking a tall glass of water four times throughout the day would wipe out nearly one hundred extra calories, more than the calories burned by taking weight-loss doses of the now-banned ephedrine three times a day. Plain, cheap, safe, and legal tap water!” – Dr. Michael Greger
Drinking lots of water is frequently associated with weight loss. Greger introduces a systematic review study where they investigated twelve studies that considered the relationship between hydration and weight loss. They found there is a clear weight loss benefit of having increased hydration. One of these benefits is actually indirect. Specifically, suppose an individual is drinking more water. In that case, they are less likely to be drinking empty calories in the form of sugar-filled sodas. Adolescents in America would reduce their average calorie intake by 235 if they swapped soda for water.
Additionally, there also appears to be a direct relationship between hydration and weight loss. A massive Harvard study tracked the diets and health of over a hundred thousand people for decades. They found that well-hydrated people burn fat more quickly. Plus, the well-hydrated individuals also produced less of an enzyme called angiotensin. Angiotensin drives the accumulation of fat. Greger recommends using your urine as a way to measure your hydration level. You should be aiming for urine that is light yellow, like the color of straw. If it is darker than this, then you know you should be drinking more water.
Negative Calorie Preloading
Eating before a meal, if you are eating the right things, can be considered negative calories. For example, research shows that people who eat an apple before a meal feel fuller and eat fewer calories overall. Therefore, try adding a low-calorie course, like a salad, to preload your meal.
“Sleep deprivation tends to lead people to overeat by about 180–560 calories a day.” – Dr. Michael Greger
Sleep is often considered essential but is neglected within fad diets. However, Dr. Greger views sleep as one of the cornerstones of effective weight-loss. Being tired is associated with eating more and making poor dietary choices. For example, studies suggest that late-evening snacking is associated with an excess of approximately 700 calories per day. Plus, studies have also found that sleeping well seems to be associated with weight loss irrespective of what you eat. Those who sleep less tend to burn more muscle than fat, even when in a caloric deficit.
If you have feedback about this summary or would like to share what you have learned, comment below.
New to StoryShots? Get the audio and animated versions of this summary and hundreds of
other bestselling nonfiction books in our free top-ranking app. It’s been featured by Apple, The Guardian, The UN, and Google as one of the world’s best reading and learning apps.
Related Book Summaries
The Plant Paradox by Steven Gundry
The Keto Reset Diet by Brad Kearns and Mark Sisson
The 4-Hour Body by Tim Ferriss
The Keto Diet by Leanne Vogel
Thinner Leaner Stronger by Michael Matthews
The Obesity Code by Jason Fung
Not A Diet Book by James Smith
Gandhi by Mahatma Gandhi