The ketogenic diet — or keto, for short — is a high-fat, low-carb regimen that has been linked to a variety of health benefits, including weight loss and lower blood-sugar levels. The trendy diet, which eschews carbohydrates in favor of fats, works by triggering a metabolic state known as ketosis.
During ketosis, as blood sugar levels plummet in the absence of carbs, fatty acids are broken down in the liver and converted into ketone bodies, another source of energy. Basically, during ketosis, cells burn excess fat, not sugar, to harness the energy the body needs to survive.
How Ketosis Feels
For keto newbies, it can be hard to know whether or not ketosis is actually taking place — but a few common signs might help. At first, many dieters experience bad breath due a particular ketone, acetone, which is expelled from your urine and breath. And then there’s the famed keto flu, which refers to short-term symptoms like weakness and fatigue that occur as people transition away from carb-heavy fuels.