Do Ketogenic Diets Really Work?

Some fads never die, right? Low carb diets were a thing in the late 90s and they’re still a thing now. But does this fad have staying power because the benefits are real? Or is that greasy low-carb burger fried in snake oil? We can try to address some of those questions with science. Low carb diets do have their place in the medical world. It just might not be where you’d expect. Before we get started, remember that we aren’t medical professionals. If you need real health and dieting advice, that’s what your doctor is for, not Youtube.

There are about as many low-carb diets out there as there are people who can get a diet book published. But right now we’re specifically talking about ketogenic diets - the ones that usually require people to eat under 50 grams of carbohydrates [On screen: sugars and starches] per day. For a normal diet, carbs deliver most of a person's daily energy. With ketogenic diets, carbs account for roughly 1/10. Eating so few carbs can kinda, sorta trick your body into thinking it’s starving, convinces your body to totally revamp its approach to energy production, and it goes into a state of metabolic uproar called ketosis. We can derive energy from carbs or fats or protein, but our giant, energy-hungry human brains have a strong preference for sugar. It’s all that thinking we all do all the time. That takes fast, digestible fuel. In fact, our brains are such picky eaters that they can’t really make use of the other stuff at all. Fats can’t even cross the blood-brain barrier.

So with your brain running out of fuel, your liver panics, and starts breaking fats down into brain-digestible molecules known as ketone bodies. In organic chemistry, a ketone is a molecule with a carbon double bonded to an oxygen, and more carbons on either side of that carbon. The ketone bodies that your liver makes are beta-hydroxybutyrate, acetoacetate, and acetone -- yes, as in nail polish remover. The acetone is actually volatile enough to escape your from bloodstream into your breath, which makes it smell sweet. So why would you intentionally go on a diet that rearranges your metabolism so dramatically? Actually, there are good reasons. For example, when people, and especially children, who have epilepsy don’t respond to drug treatments, getting put on a ketogenic diet can help manage symptoms for huge numbers of patients. But it doesn’t work for everybody. Brains and diets are two of the most complicated and poorly understood things about the human body. So even though it’s clear that ketogenic diets help with epilepsy, despite tons of research, we still don’t understand exactly WHY.

One leading hypothesis is that keto diets help switch on the neurotransmitter GABA. GABA is responsible for generally calming things down in your brain, so it stands to reason that more inhibitory activity would tamp down seizures. Another hypothesis is that ketone bodies themselves can help protect against seizures. But while there’s evidence for a bunch of different ideas, like we said -- brains. Diets. Complicated. It doesn’t stop with epilepsy. Keto diets seem to have a protective effect on the brain, and diseases from Alzheimer’s to ALS could stand to benefit. This is an active area of research, so don’t expect a keto diet to cure Parkinson’s tomorrow.

But the main reason most people go on a keto or other low carb diet is to lose weight. Nothing wrong with that, but can a ketogenic diet help? Some studies say it can. When researchers rounded up the effects of multiple studies of keto diets compared to traditional low fat diets, it seemed like people lost more weight, although their cholesterol went up more too. Keto diets reduce your body’s level of insulin, which helps you feel full and might explain that weight loss. Low insulin can also lead to ketoacidosis, which is different from ketosis. It’s a dangerous condition where blood ketone levels are high and pH is low, and it’s mostly people with diabetes who are at risk.

But that’s a whole ‘nother video. It seems clear from clinical studies that keto can help people lose weight, but because diets are complicated, we don’t quite know how. It might be because the process of breaking down fats is less efficient than breaking down carbs, so more of the energy you eat actually gets wasted -- instead of going to your waistline. But, like with any diet, keto works a whole lot better under a doctor’s supervision and with careful adherence to the rules.

And ketosis can be a double edged sword, with side effects like brain fog and fatigue in the first few weeks. In fact, keto diets require a drastic change in lifestyle for most people. The weight loss benefits could end up being only as strong as your ability to stick to bunless burgers day in and day out. Doctors might hesitate to recommend keto on this basis and put patients on a low fat diet instead. But low carb diets are something your body can totally deal with, thanks to the chemistry of ketones. And from our brains to our love handles, those lil guys seem to be on our side -- most of the time.

Remember to share and subscribe on your way out, and thanks for watching. Pinned comment: Have you tried going low or no carb? Did it work for you? Or do you find fad diets to be so much bacon grease -- smells good, but doesn’t deliver?.