Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...Tell Me More
As someone interested in the world of keto, you’ve likely heard (or read) about it’s amazing potential for weight loss, mental sharpness and more! A well-designed ketogenic diet is a virtually unmatched tool for managing your weight (and many chronic health conditions) as well as supporting your cognitive acuity and overall healthy aging regimen.
Notice, however, that I said well-designed ketogenic diet….
With the exploding popularity of the keto diet, you’ll undoubtedly find countless approaches and tips out there focusing only on increasing fat consumption or avoiding carbohydrates at any and all costs. These strategies, in my experience, miss the bigger picture of what keto should be—and what is possible with the keto diet.
Keto is a loose term to describe a whole host of very low carb diets. The underlying commonality (and sometimes the only one) among many “keto” approaches is low carbohydrate intake. Within that definition, some suggest as little as 10-20 grams of carbohydrates per day. Others, like the Keto Reset Diet, allow for 50 grams (and in some cases more).
The key is to get carb intake low enough that the liver produces ketones (now you know where the name comes from), a source of energy that most of the body—including the brain— can use for fuel.
Most of the time, particularly with the Standard American Diet, we’re running our bodies on glucose from the carb sources we regularly eat throughout the day. When carb intake is restricted enough, the body needs to tap other energy sources. That can include fat and ketones. While much of the body can use fat efficiently, the brain does not—hence the need for ketone production under a very low carb scenario.
Rather than understand this setup from a restrictive perspective, a look into human evolutionary history shows us this would’ve been a common if not default arrangement. Our hunter-gatherer ancestors didn’t have regular access to much carb intake beyond seasonal fruits or tubers. They spent much of the time operating in ketosis—the metabolic state of producing ketones as a fuel source in the context of carb restriction. Our bodies today fully retain this ability, and there are substantial benefits from a lifestyle that incorporates that full metabolic flexibility.
The Keto Reset Diet is a particular approach to keto that prioritizes nutrient density and natural, whole food eating. It’s the approach I myself live (and promote) because it’s a sustainable means of achieving and maintaining ketosis without compromising overall nutrition or health.
In other words, you get all the metabolic advantages of ketosis (lower insulin levels, lower inflammation, more” even” energy and cognitive function, etc.) AND the critical benefits of a nutrient-dense diet. With the general suggestion of 50 grams of carbs per day, the Keto Reset Diet offers a generous window to enjoy a flavorful, varied diet every single day.
Watch the video below to learn more about the Keto Reset approach to ketogenic eating….
The ketogenic diet first emerged as a tool for clinicians to treat their patients with epilepsy. It was—and remains—the only thing with the consistent ability to prevent seizures.
Keto’s effects on neuronal function and health, along with the ability of aging or degenerating brains to accept and utilize ketone bodies, also have implications for other brain conditions, such as Parkinson’s, Alzheimer’s and even certain psychiatric disorders.
A ketogenic diet also appears to improve memory and cognition in those with minor declines in these area.
Since ketosis can help with major brain disorders, many have wondered whether it can improve cognitive function in otherwise healthy people. Although research is still scant in that area, many people report a profound sense of mental clarity once they’ve successfully transitioned to a keto diet. Unfortunately, researchers haven’t studied the nootropic effects of ketogenic diets in healthy people—yet. They have looked at people with “milder” cognitive deficits, though, finding some promising effects.
The ketogenic diet is increasingly used to treat metabolic disorder. Because maintaining a ketogenic diet reduces blood sugar levels, it’s a natural strategy for treating diabetes and even potentially reversing pre-diabetes. More research is underway to illuminate the effectiveness of keto for those with metabolic disorders.
In cancer patients, a keto diet preserves lean mass and causes fat loss. Many researchers are exploring the use of ketogenic diets in preventing and treating cancer, although results are very preliminary.
Being keto-adapted has several advantages for anyone interested in physical performance.
It increases energy efficiency. It also spares glycogen. Glycogen is high-octane fuel for intense efforts. We store it in the muscles and liver, but only about 2400 calories-worth—enough for a couple hours of intense activity at most. Once it’s gone, we have to carb up to replenish it. Keto-adaptation allows us to do more work using fat and ketones for fuel, thereby saving glycogen for when we really need it. Since even the leanest among us carry tens of thousands of calories of body fat, our energy stores become virtually limitless on a ketogenic diet.
It also builds mitochondria. Mitochondria are the power plants of our cells, transforming incoming nutrients into ATP. The more mitochondria we have, the more energy we can utilize and extract from the food we eat—and the more performance we can wring out of our bodies. Ketosis places new demands on our mitochondria, who adapt to the new energy environment by increasing in number.
Although keto is not a classical weight loss diet, it can certainly help a person lose body fat. After all, to generate ketones without eating ketogenic precursors, you have to liberate stored body fat.
But that’s not the main mechanism for ketogenic fat loss. Ketosis isn’t “magic”—it doesn’t melt body fat away. Instead, it works for many of the same reasons a standard low-carb Primal way of eating works: by reducing insulin, increasing mobilization of stored body fat, and decreasing appetite.
Many diets work in the short-term and fail in the long run. Weight loss isn’t worth anything if you can’t keep it off. Ketogenic diets appear to be good for long-term maintenance of weight loss.
The bulk of your food intake (in terms of volume) should come from “above-ground” vegetables—those that grow above the ground like greens, peppers, broccoli, Brussels sprouts, cauliflower, tomatoes, celery, cucumber, kale, cabbage, asparagus, zucchini, mushrooms and avocado.
You’re also free to enjoy virtually any fish or meat that doesn’t contain added breading or sweeteners. Eggs are also an ideal choice. In fact, many people often don’t eat enough protein while trying a keto diet. While an overabundance of protein can inhibit ketosis, this isn’t an issue most people would deal with. The average American, particularly older men and women, don’t eat enough protein for their muscle maintenance needs. Bone broth and collagen supplements that don’t contain carb sources like sugars, fillers or binders are also healthy choices while keto.
The majority of your calories on a keto diet will come from fat. Choose healthy sources like avocado, avocado oil, extra virgin olive oil, full-fat cheese, butter or cream, as well as fattier cuts of meat like “dark meat” poultry and fatty fish like salmon.
Nuts can be eaten in moderation, as they contain healthy fats and a minor amount of protein.
For drinks, coffee and teas without sugar, unsweetened sparkling water and mineral water are ideal choices.
In short, you’ll want to avoid empty carbs of all kinds. I like to look at healthy eating, and particularly health keto, as the optimization of carb sources. Foods and drinks with a high carb count and little nutrient value are obvious choices to avoid: sodas, juices, sweetened nut milks, candy, baked goods, and other sweets and grain-based foods.
For the sake of maintaining ketosis, it’s also important to avoid most legumes (like beans and peas) and starchy vegetables (like potatoes, sweet potatoes and squashes) as well as dairy items of a higher carb count (like yogurts and milk).
Ketogenic dieting is a big jump for some people. You’re literally switching over to a new metabolic substrate. That can take some getting used to. Make sure you are well-prepared with a Primal-aligned eating pattern in place for ideally several weeks before you ponder a journey into nutritional ketosis.
Make a minimum commitment to six weeks of nutritional ketosis. You’ll want to allow ample time for the transition to new fuel sources. Six weeks will put the metabolic machinery in place and allow you to begin experiencing the most dramatic benefits of keto living.
Get plenty of electrolytes. You’ll want lots of sodium, magnesium, and potassium. Try 4.5 grams sodium (about 2 teaspoons of fine salt or a little under 3 teaspoons of kosher salt), 300-400 mg magnesium, and 1-2 grams of potassium each day on top of your normal food. Going keto really flushes out water weight, and tons of electrolytes leave with it.
Eat extra fat during the first week to accelerate keto-adaptation. Just be sure to dial fat intake back after the first week or two.
Do lots of low level aerobic activity. Walk, hike, jog, cycle, row. Keep things in the aerobic HR zone (under 180 minus age in heart beats per minute), and you’ll increase your utilization of body fat, which will speed up ketone production and adaptation.
Eat fiber. Many people on ketogenic diets tend to ignore fiber. That’s a mistake. Fiber doesn’t digest into glucose. It also supports your gut biome.
Finally, it’s important to share that, as with any new dietary regimen, it’s important to consult your doctor—particularly if you have an existing health condition.
I don’t recommend keto for women who are pregnant or nursing or for teens and young adults who are still growing, unless directed and supervised by a physician. For more on keto precautions, check out this page.