People adopt ketogenic diets for many different reasons, but weight loss is near the top of the list. And while some people drop weight seemingly effortlessly when they cut carbs, others struggle to shed excess pounds. Let’s look at the five most common reasons for slow or stalled weight loss on keto diets.
1. Consuming too much carbohydrate
As we covered in a previous article, the top two things that get in the way of fat loss on keto are overdoing carbohydrate intake and going overboard on dietary fat. When losing body fat is the main goal, there’s no need to focus on “macros” (percentages of calories from protein, fat, and carbohydrate) or on maintaining any particular ketone level. What facilitates the body’s transition from burning mostly glucose to burning more fatty acids is a lower insulin level, which is prompted primarily by a lower carbohydrate intake. While it’s possible to overdo total carbohydrates from non-starchy vegetables, dairy products, nuts and seeds, the biggest culprits tend to be things like ice cream, cereal, bread, cookies, and similar items marketed as “keto” or “keto-friendly” despite having a high carbohydrate load.
A simple fix for this roadblock is to switch from counting net carbs to counting total carbs. When total carbs are counted rather than net carbs, grams of carbohydrate from fiber and sugar alcohols are not subtracted, so it’s a stricter and often more powerful approach to the diet.
2. Overindulging in dietary fat
People can be led astray when they hear keto referred to as a “high-fat diet.” Compared to what people were eating before they started keto, they may be consuming a higher percentage of their calories from fat, but it’s not necessary to drown every bite in melted butter or to drizzle oil over everything. Metabolizing fat and being fueled primarily by fatty acids isn’t the same thing as losing body fat. Keeping carb intake very low facilitates burning fat – but if dietary fat is overconsumed, then the body has no need to tap into its stored fat, which is what needs to happen if someone wants to lose weight.
Two main things likely lead to people erring on the side of an excessive fat intake. First, they’ve heard through social media that they need to have a certain “fat macro” and deliberately add extra fats and oils to their food in order to reach that. Second, they may be coming from a history of low-fat diets, and having the freedom to enjoy butter, cream, coconut oil, bacon and other fatty meats, may be a welcome change that they inadvertently go overboard with.
There’s a simple corrective step for this: go easy with added fats and oils. Most people can enjoy fatty cuts of meat (steaks, pork chops, etc.) and still lose weight on keto. Heavy cream, butter, and a heavy hand with mayonnaise and oils are more common things that get in the way of fat loss – even when carbohydrate intake is very low. Some people may find that fat loss happens more easily when they eliminate dairy foods or are more mindful of the total amount they consume. Cheese is a common trigger food that can be difficult to stop eating after just a small portion. For many, it’s easier to have none than it is to stop after just a couple of ounces. The same is true for nuts and nut butters. It’s the rare person who can be satisfied with just one ounce of almonds or one spoonful of peanut butter! These items are very high-calorie and are nearly effortless to overconsume.
3. Weight-positive medications
When someone is diligent about their carbohydrate and fat intake and stubborn weight still isn’t budging, the next thing to address is medications that are known to cause weight gain or that may make it more difficult to lose any. The list of these is long and varied. Frequently prescribed ones include psychiatric medications, certain diabetes drugs, and steroids, although there are numerous others. (See here for a list from the Obesity Medicine Association.)
The good news is, by following a keto diet, some people may be able to reduce doses and eventually completely discontinue some of their weight-positive medications. Ketogenic diets can help to put type 2 diabetes into remission and have also led to unprecedented improvements in mental illness, so adhering to this way of eating may enable people to titrate down or eliminate some of the medications that are standing in the way of fat loss. (The cardiometabolic benefits of keto diets can be realized even in the absence of clinically meaningful weight loss. When improved physical or mental health comes first, weight-positive medications may be able to be reduced, allowing weight loss as a second order effect.)
4. Suboptimal thyroid hormones
Undiagnosed or inadequately treated hypothyroidism is a common reason for a lack of fat loss on keto. With thyroid hormones—T3, specifically—having a powerful influence on basal metabolic rate, weight loss can be a losing battle if these are not at optimal levels. As we detailed in a past article, the standard TSH test (thyroid stimulating hormone) is often not sufficient for identifying suboptimal thyroid hormones. When a patient’s blood tests look great – fasting glucose and insulin are at a healthy normal level, HbA1c and the triglyceride-to-HDL ratio are optimal, and other cardiometabolic markers look good, that’s strongly suggestive that someone is adhering to keto. So if weight is still stubborn—particularly if they have other signs and symptoms of low thyroid—it may be helpful to order a comprehensive thyroid panel.
Many people who struggle with fat loss even while faithfully sticking to keto may also be taking antidepressant medication and/or a statin drug, when depression and elevated cholesterol can be indicative of low thyroid. (There’s a striking link between undiagnosed or improperly treated hypothyroidism and depression.) Women are afflicted with hypothyroidism far more often than men – in about a nine-to-one ratio. Women with a history of yo-yo dieting may be especially susceptible to suboptimal thyroid hormones (in particular, low T3 and possibly elevated reverse T3) even with a normal TSH. A small dose of T3 (liothyronine) may be enough to correct this metabolic slowdown, but some patients may require higher doses. Levothyroxine (T4) alone may be sufficient for some patients but the conversion from T4 does not happen adequately in some people and they may need additional T3 therapy to get the desired outcome.
5. Impatience and comparison
Sometimes “tincture of time” is all that’s required to get stubborn excess pounds to pack their bags and say goodbye. It’s easy to be misled by seemingly miraculous—and fast—transformations on social media. And while keto does lead to rapid fat loss in some individuals, for others it simply takes more time. Younger people tend to lose more quickly than older folks, and men typically have an easier time losing weight than women do … even when men don’t adhere to keto as strictly. And the more weight someone is looking to lose, the more quickly it tends to come off at first, compared to the rate of loss in people who are looking to lose only a few pounds. Expecting weight loss to be immediate and impressive can lead to disappointment, frustration, and eventually giving up altogether.
It’s important to avoid playing the “compare and despair” game. Expecting results to be the same as someone else’s can be demoralizing and can lead to a false conclusion that keto “isn’t working.” Slow weight loss is still weight loss! And whether weight loss is happening or not and frustration and impatience are still at the forefront, it can help to focus on all the non-weight-related benefits keto may bring: less heartburn, fewer and less severe migraines, improvement in skin conditions, improved polycystic ovarian syndrome (PCOS), and improvement in type 2 diabetes and hypertension such that medications may need to be reduced or discontinued.
Recognizing that keto brings so many benefits even when weight loss is slow or stalled can help patients stay motivated and enthusiastic about staying on plan. And that’s an essential part of success with any way of eating, not just keto: it only works if you actually stick to it!