{"id":17016,"date":"2025-12-28T09:37:33","date_gmt":"2025-12-28T17:37:33","guid":{"rendered":"https:\/\/foodrevolution.org\/?p=17016"},"modified":"2026-03-12T08:05:00","modified_gmt":"2026-03-12T15:05:00","slug":"what-is-the-keto-diet","status":"publish","type":"post","link":"https:\/\/foodrevolution.org\/blog\/what-is-the-keto-diet\/","title":{"rendered":"The Keto Diet Explained: What the Science Really Says"},"content":{"rendered":"

In recent years, the \u201cketo\u201d diet has attracted millions of people looking to lose weight and reap its other purported benefits. So, are they onto a cutting-edge biohack? Or dangerously misguided, trading short-term results for long-term misery?<\/p>\n

What is the Ketogenic Diet?<\/h2>\n

There are a few different kinds of ketogenic diets (more on that later), but what they all have in common is a severe reduction in carbohydrate intake, putting your body into a metabolic state known as ketosis.<\/p>\n

Ketosis occurs when your body metabolizes fat rather than carbohydrates to produce energy. This process produces ketones \u2014 a type of acid \u2014 in your blood as a by-product.<\/p>\n

It\u2019s actually pretty cool that our bodies can do this. It was once<\/a> a useful survival tool for our ancestors.<\/p>\n

We wouldn\u2019t have made it as a species without our body\u2019s ability to temporarily use fat when we couldn\u2019t find enough carbohydrate-rich foods. Stored fat got our ancestors through hard times when food was scarce and provided a buffer when they had to go days without eating.<\/p>\n

As this process existed as an evolutionary tool, there\u2019s even evidence<\/a> that challenging the body through fasting-induced ketosis every so often yields health benefits. The fancy term for this phenomenon is \u201chormesis<\/a>,\u201d meaning certain stressors in certain doses at certain intervals can actually make us stronger. (Lifting weights to break down muscle fibers is a familiar example of hormesis in action.)<\/p>\n

But the modern ketogenic diet movement, as we know it, doesn\u2019t typically focus on temporary or intermittent fasting as a survival tool. The keto diet seeks to keep the body in a permanent state of ketosis by severely restricting carbohydrates and compensating with loads of fat and protein as an energy source.<\/p>\n

So what exactly do you eat on a ketogenic diet, and what are you supposed to avoid?<\/p>\n

Foods Not Allowed on a Ketogenic Diet<\/h2>\n
\"Carbohydrates
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Carbohydrates are the enemy on a keto diet. That includes sugary foods, grains and starches, alcohol, most fruit, beans and legumes, root vegetables and tubers (e.g., sweet potatoes, beets, carrots), low-fat or diet products, and some condiments or sauces. In fact, your carbohydrate consumption might be less than you\u2019d derive from a single apple a day.<\/p>\n

But a ketogenic diet doesn\u2019t distinguish between \u201cgood carbs\u201d like lentils and \u201cbad carbs\u201d like lollipops. <\/span><\/p>\n

While it\u2019s great that it eliminates refined sugar, white flour, and many processed foods, keto also forbids some of the healthiest foods on the planet.<\/p>\n

Avoiding whole, plant-based carbs like <\/span>fruit<\/span><\/a>, <\/span>legumes<\/span><\/a>, and grains means that you\u2019re likely to be dangerously deficient in <\/span>antioxidants<\/span><\/a>, <\/span>phytochemicals<\/span><\/a>, vitamins, and minerals, all of which are important for disease prevention and long-term health.\u00a0<\/span><\/p>\n

You\u2019ll also likely miss out on adequate <\/span>fiber<\/span>,<\/span><\/a> which is no small matter. About 97% of the US population is already <\/span>deficient<\/span><\/a> in fiber, which puts you at increased risk of <\/span>heart disease<\/span><\/a> and several <\/span>digestive cancers<\/span><\/a>, as well as <\/span>breast cancer<\/span><\/a>.\u00a0<\/span><\/p>\n

So What Can You Eat On A Ketogenic Diet?<\/h2>\n
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Keto-compliant foods include meats<\/a>, fish<\/a>, eggs<\/a>, butter and cream, nuts and seeds<\/a>, vegetable oils<\/a>, avocados<\/a>, low-carb veggies (e.g., lettuce, zucchini, and peppers), and certain condiments.<\/p>\n

Eating plant-based fats<\/strong> from nuts, seeds, and avocados does make <\/span>good sense<\/span><\/a>. And plenty of studies show us that low-carb vegetables (like <\/span>leafy greens<\/span><\/a>) are terrific health boosters. The problem is that, for most keto diet adherents, a majority of their calories typically come from animal products.\u00a0<\/span><\/p>\n

Given the overwhelming body of evidence linking consumption of meat and other animal products to <\/span>cancer<\/span><\/a>, <\/span>Alzheimer\u2019s<\/span><\/a>, and <\/span>heart disease<\/span><\/a>, the fact that keto diets typically rely heavily on animal products seems like a recipe for long-term health problems.<\/span><\/p>\n

Types of Ketogenic Diets<\/h2>\n
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There are five main types of ketogenic diets:<\/span><\/p>\n