Keto. Everybody's doing it, or at least hashtagging about it. But what is it? Does it work? And why should you give up all the carbohydrate pleasures in this world to be a part of it? The answer, of course, is complicated.
What is Keto
Ketosis is actually a pretty rad thing. It's thought to be an evolved mechanism that allowed humankind to stay (relatively) healthy and functioning in times of famine or during long northern winters that were inhospitable to growing carbs (ie: fruits, vegetables, and grains). When the body is starved of carbohydrates, blood glucose -our body's primary energy source- dries up (figuratively). When glucose is severely limited over an extended period of time, the body responds by concocting little balls of energy called ketones, manufactured from fatty acids. These fatty acids come both from the diet and from the body's stored fat. What's unusual here isn't that the body is burning some fat, but that this particular form of fat is able to cross the blood-brain barrier and provide energy to the brain. It's not the simplest process for the body, but as more and more ketones are made, the body becomes more and more efficient at it. The better it gets at the process, the more stable and sustained the energy becomes. Brain function remains high and clear because "hanger" and low blood sugar crashes are things of the past.
When you're running on ketones, eating fat is like throwing a big, hearty log on the fire as opposed to a pile of snappy kindling (these would be carbs). Snack breaks become a thing of the past and mealtimes may pass without a hunger-signal peep from the body. Pounds melt away while brain function hits all-time highs.
Sounds pretty glorious. It can be. But...
Getting into a ketogenic state is a serious matter. While bio-individuality means we all have different thresholds of macronutrient needs, it generally requires a diet very high in fat, or 60-80% of your caloric intake. Protein usually comes in at a cool 15-30%. It must be kept low enough that the body doesn't decide to turn some of it into glucose and weasel its way around your ketogenic dreams. Carbs are limited to 5-10% of calories, or somewhere south of 50 grams. Carb-wise, this translates into few or no grain products and fruit, but a generous amount of vegetables. If you're thinking "Atkins" and "low-carb" at this point, note that the cap on protein intake and hefty fat requirement is a significant difference that can make or break true ketosis.
How do you know if you're doing it right?
There are a variety of ways to find out if you're in ketosis. One is by listening closely to your body. Are you eating super high fat/low carb and feeling energetic, clear, and satiated? Sounds like ketosis. Weird tasting breath is another sign that the body's burning fat and is usually described as fruity or sweet. Urine test strips can be used for a definitive confirmation; these are easily found online or at pharmacies and are usually marketed towards diabetics concerned about ketoacidosis, a different and dangerous state than the ketosis we're discussing. Ketone blood tests are also available if you want to know more specific details.
Should I try it?
This is where it gets complicated. For every individual loving their keto freedom, there's another that will never, ever go back to that dark place. What gives?
Women of child bearing age may be especially impacted by ketosis. Despite a clear mind and constant, cool energy, healthy hormone production may take a serious hit. This is because for women, fertility is a carefully monitored process that depends on adequate calories and a macronutrient balance. Some have theorized that this response to a lack of carbohydrates may also be evolutionary; carb shortages would hit at the tail end of a long winter, exactly when conception would result in a baby born at the start of another cold, hard winter. If fertility signed off in response to this seasonal carb shortage, the birthing season would conveniently skip the worst months when food is scarce and temps are low.
Thyroid hormones play a big role in fertility and these sometimes take a direct hit from a low carbohydrate diet. Sensitive individuals may carb-starve themselves into a hypothyroid state, which means lowered energy, slower metabolism, stunted libido, and more. Insulin resistance is another possible -though infrequent- side effect. While a ketogenic diet usually improves all things blood-sugar-related, some people seem to lose the ability to handle carbs at all.
Note that these conditions are reversible with some careful carb rehab.
It's interesting to note that men, in general, do better than women on a ketogenic diet. This also may have an evolutionary tie; a man with an uncertain food supply has more reason to be fertile and spread DNA as much as possible.
A Lean, Mean, Ketosis-Machine
Fitness-wise, ketosis is an interesting animal. When followed long-term, many fitness buffs discover a frustrating decrease in muscle mass. This is the natural result of a low protein intake and may be offset by cyclic eating (more on that later). Those who enjoy higher cardio activities or racing might discover a decrease in speed because carbohydrates provide the "quick burn" fuel responsible for extra snazzy muscle contractions. Boosting carbs on race day can work around this problem. Endurance athletes, on the other hand, benefit the most from the sustained energy that ketosis provides. Because the body can store oodles more energy in the form of fat than glucose, ketosis for the endurance athlete means no bonking, less refueling, and longer stamina.
So what does all of this mean if you're keto-curious and just looking to feel good and drop a few pounds? Give it a whirl! Try it on for size. But do it wisely and treat with caution. Do your homework and learn how to properly balance a ketogenic intake. Do not mistake all fat for good fat; choose high quality animal fats, grass-fed dairy fats, whole nuts and seeds, cold-pressed oils, and -of course!- a coconut-derived MCT oil. It's normal to feel less than radiant in the first few weeks as your body adjusts to its sudden carb starvation, but expect for that to shift into a ketone-enlightened state within a month. If you don't experience improvement, ketosis might not be your thing.
Can you hack the benefits?
There is a grey zone called "versatile metabolism" that we should all strive to tap into. This means is that the body burns plenty of glucose, but is also efficient at tapping into fat stores if glucose is low. Sounds simple, but many of us are incredibly inefficient at burning fat. If you experience low blood sugar on the reg, this means you.
The easiest step towards fixing this is by taking advantage of your sleep. For many of us, the 8-ish hours we spend snoozing is the longest we go between meals. Our body, ever burning, eventually depletes its glucose supply and has no choice but to grudgingly burn some fats. Typically this is the state that we wake up in; low blood sugar, fat burning wheels slowly turning.
If your breakfast provides adequate carbohydrates in the form of, say, breakfast cereal, toast, or fruit, our glucose stores are refilled and our body cheerfully resumes burning sugar. If instead you choose a high fat/moderate protein/low carb breakfast, you encourage it to continue burning fats, as they become the most available source of energy. In this case, short and medium chain fatty acids, like those found in butter and coconut oil, are helpful for their easy-access energy. If you're thinking "bulletproof" or "butter coffee" right now, you're right on track. With time and commitment, sticking to a high fat/low carb breakfast and up-tapering carbs later in the day can do wonders for your blood sugar control and metabolism.
Another option is to cycle by days, eating a ketogenic diet for 3, 4, or 5 days at a time and a more protein/carb-rich diet on the off days. Keep in mind, however, that some people do better on an all-or-nothing ketosis approach, at least at the start. A body that struggles to produce and run off of ketones may rely on higher carb days as refreshing crutches and never fully adapt to fat metabolism.
So, so much more can be said about the ketogenic diet. Everyone who's tried it has their own unique ketogenic anecdotes. The primary take-home I leave you with is that ketogenic success is individual and variable. While the benefits are strong enough that it might be worth trying, you must also keep an eye peeled for the possible negative effects, like hormone changes or blood sugar regulation issues. This is fodder to discuss with your personal health team.