But there is evidence that low-carb diets may increase metabolism, according to a paper published November 14 in BMJ. Researchers found that overweight adults who lowered carbohydrates and added more fat into their diets burned about 250 calories more each day than people on high-carb, low-fat diets. The study is impressive because it's the largest, most expensive, and controlled study of its kind.
“I am a physician with type 1 diabetes. I have been using a low-carb, ketogenic diet to treat my own diabetes for the past 16 years. Evidence shows that low-carb diets are safe and effective. With the potential to reverse type 2 diabetes, control type 1 diabetes and even stop, slow down, or reverse complications, a low-carb diet can be life changing. Diet Doctor provides the most accurate and relevant materials for a healthy, easy and fun low-carb experience.”
While you’re focusing on fat, protein, and carbs, you should also make sure you’re getting adequate fiber. “People often assume that they should only eat things like meat and butter on the ketogenic diet,” says Farshad Fani Marvasti, MD, an associate professor and director of Public Health, Prevention, and Health Promotion at the University of Arizona College of Medicine in Phoenix. “You should make sure you are eating enough vegetables because you need the fiber.”
In general, you want to eat the minimum amount of protein to preserve lean body mass and not overtax your kidneys. If you eat too much protein, the excess converts to glucose through a process called gluconeogenesis. You don’t want that to occur in ketosis. Instead, eat anti-inflammatory protein—at the minimum amount to preserve or build lean body mass. My favorite sources are wild-caught fish, grass-fed and -finished beef and wild meats (elk, bison, etc.), pasture-raised poultry, nuts, and seeds. Make sure fish has more selenium (which helps protect the brain) than mercury, to mitigate heavy metal toxicity. Good sources that have a safe selenium/mercury ratio include: tuna, opah, wahoo, spearfish, swordfish.
Many unhealthy foods easily meet keto’s low-carb, high-fat criteria. However, that doesn’t mean you can or should eat them freely. “A huge benefit to following the keto diet is that the vast majority of processed food is removed with the removal of grains,” Santo says. “Unfortunately, poor-quality dairy, meat, and veggies may fill the gap.” Look for healthier sources of protein and fat, such as grass-fed meats, and limit processed dairy (think cheese singles) as much as possible.
When your body goes into ketosis, it will start to produce by-products called ketones. This includes acetone—yes, the same chemical found in nail polish remover, which your body actually naturally makes on its own, according to a 2015 review of research. Because acetone is a smaller molecule, it tends to make its way into your lungs. You’ll eventually exhale them out, resulting in “keto breath.” Your mouth might also have a metallic taste, but it won’t last forever as you adjust to the diet. Just be diligent about brushing your teeth!
“I have been a supporter of a low-carb lifestyle that includes intermittent fasting for myself and my patients for years. I am part of our health systems Medicine Residency program. I teach physicians-in-training and medical staff to utilize low-carb and keto dieting to improve the health of their patients and reduce their need for medications. Diet Doctor is an excellent resource for patients and physicians to help patients help themselves to promote a healthy lifestyle.”
Early studies reported high success rates; in one study in 1925, 60% of patients became seizure-free, and another 35% of patients had a 50% reduction in seizure frequency. These studies generally examined a cohort of patients recently treated by the physician (a retrospective study) and selected patients who had successfully maintained the dietary restrictions. However, these studies are difficult to compare to modern trials. One reason is that these older trials suffered from selection bias, as they excluded patients who were unable to start or maintain the diet and thereby selected from patients who would generate better results. In an attempt to control for this bias, modern study design prefers a prospective cohort (the patients in the study are chosen before therapy begins) in which the results are presented for all patients regardless of whether they started or completed the treatment (known as intent-to-treat analysis).
Commonly known as “keto”, a ketogenic diet is a diet typically characterized by a 4:1 ratio of dietary fat to protein and carbohydrate and was originally used in the treatment of childhood epilepsy. It has been theorized that keto diets facilitate greater fat loss in humans as an absence of dietary carbohydrate forces the body to oxidize fat as its primary energy source.
I personally don't follow a very low-carb diet because I have such a preexisting condition which may have been caused by my calorie-restricting dieting many years ago. My "ideal" level is somewhere around 30 grams of net carbs (light ketosis). By "ideal" I mean a level at which I feel great and maintain a healthy weight. I sometimes eat less carbs out of habit, not because I force myself to follow a very low-carb diet. Following a very low-carb diet (less than 20 grams of total carbs) doesn't help in my case: it made no difference to my appetite or energy levels but I felt worse. You simply need to try it yourself and find your "ideal" carb intake.
A ketogenic diet could be an interesting alternative to treat certain conditions, and may accelerate weight loss. But it is hard to follow and it can be heavy on red meat and other fatty, processed, and salty foods that are notoriously unhealthy. We also do not know much about its long-term effects, probably because it’s so hard to stick with that people can’t eat this way for a long time. It is also important to remember that “yo-yo diets” that lead to rapid weight loss fluctuation are associated with increased mortality. Instead of engaging in the next popular diet that would last only a few weeks to months (for most people that includes a ketogenic diet), try to embrace change that is sustainable over the long term. A balanced, unprocessed diet, rich in very colorful fruits and vegetables, lean meats, fish, whole grains, nuts, seeds, olive oil, and lots of water seems to have the best evidence for a long, healthier, vibrant life.
Aude, Y., A. S, Agatston, F. Lopez-Jimenez, et al. “The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat: A Randomized Trial.” JAMA Internal Medicine 164, no. 19 (2004): 2141–46. doi: 10.1001/archinte.164.19.2141. jamanetwork.com/journals/jamainternalmedicine/article-abstract/217514.
More importantly they measured markers of heart disease risk, including cholesterol ratios and triglycerides, blood pressure, carotid intima-media thickness (CIMT). The carotid arteries are the ones that run on both sides of the neck, where some feel to check for a pulse and determine if someone is dead. The inner walls of that artery are measured by ultrasound.
I get many questions about intermittent fasting, the health benefits, the weight loss benefits, and the like. People normally use intermittent fasting for both the energy and mental clarity it can offer. But it’s not just good for that. It can offer breakthroughs of plateaus and even benefits in nutrient uptake in exercise. We go more in depth to intermittent fasting in Week 3 and 4, so keep your eyes peeled!