Keto vs. Low-Carb Diet: Everything You Need to Know
The keto diet and a low-carb diet revolve around the same basic idea: Reduce carbohydrate intake to lose weight and improve health. Both diets are popular, both have been scientifically studied, and they share many pros and cons.
Given this, you might wonder how they’re any different — the answer lies in flexibility. This guide covers everything you need to know about keto versus low carb and will help you decide which one is right for you.
What are the keto and low-carb diets?
Keto and low-carb diets both involve restriction of carbohydrates, primarily from grains, processed foods, fruits, and starchy vegetables. While the premise behind each diet is the same, you should know about some key differences between the two.
Keto Diet Overview
The keto diet is a very low-carb, high-fat diet that aims to send your body into ketosis, a metabolic state in which your body produces a substance called ketones (also called ketone bodies). Ketones come from fat in your liver, and your body only starts to produce them when it doesn’t have enough carbohydrates to use as fuel. Advocates of the keto diet believe that this metabolic state is the most beneficial and allows your body to run at an optimal level.
Low-Carb Diet Overview
A low-carb diet also focuses on slashing carbohydrate intake, but not as sharply as the keto diet does. Low-carb diets focus on eating lots of whole foods, such as lean protein, vegetables, eggs, and healthy fats, while restricting carb-heavy foods such as grains, sugary beverages, and processed foods.
Keto vs. Low-Carb Diet: Similarities
The keto diet and low-carb diets have a lot in common. On both diets, you cut your carbohydrate intake to a small percentage of your daily calorie consumption and focus on eating whole foods.
Both diets discourage processed foods, such as crackers, chips, candy, and other snacks. You’ll increase your protein and fat intake on either diet to make up for the calories lost from carbohydrates. Both keto and low-carb plans emphasize foods like avocados, eggs, nuts, seeds, fatty fish, and healthy oils.
Keto vs. Low-Carb Diet: What’s the Difference?
A true keto diet consists of fewer than 50 grams of carbs per day, because that’s the point at which most people enter ketosis. A low-carb diet, on the other hand, may hover anywhere from 10 to 30 percent carbohydrates (about 50 to 150 grams) , but there’s no set definition of what a low-carb diet constitutes in terms of macronutrient ratios.
Depending on what percentage of your diet you allocate to carbohydrates, you may enjoy greater variety and flexibility with a low-carb diet than a keto diet. With 150 grams of carbs, for instance, you can still eat some fruits, starchy vegetables, beans, and legumes; whereas the 50 grams allowed on the keto diet don’t leave room for much other than non-starchy vegetables.
|Dairy||Very limited choices, e.g., full-fat butter||Full-fat only|
|Artificial (zero-calorie) sweeteners||Yes||Yes|
|White and brown sugar||No||No|
|Alcohol||Yes, liquor or low-carb beer||Yes, liquor or low-carb beer|
|Coffee||Yes, with low-carb or zero-sugar cream||Yes, with low-carb or zero-sugar cream|
|Processed, packaged food||No||No|
|Nuts and seeds||Yes||Yes|
Is Keto or Low-Carb Better for Weight Loss?
Studies show that both low-carb and keto diets can aid in weight loss, although some research suggests that the weight loss from these diets occurs from overall calorie reduction, not just carbohydrate reduction.
Many studies on the keto diet and weight loss show that keto is effective for inducing weight loss and supporting short-term weight loss, but that weight loss often peaks after a few months and is likely to come back if ketosis isn’t sustained.
Keto diets are known to spur rapid weight loss in the first couple of weeks, but that doesn’t come without a cost: Many keto dieters go through the “keto flu,” a condition that feels much like the real flu (complete with nausea, fatigue, and headaches) as your body adjusts to the state of ketosis.
Because of the higher carb allowance and thus more food variety on low-carb diets, they are often more sustainable than keto and, while it might take longer to lose the first 10 pounds, makes it easier to keep the weight off for the long-term.
Summary: Keto induces rapid weight loss but might be hard to sustain, while low-carb diets help you lose weight over the long term.
Is Keto or Low-Carb Better for Fitness?
There’s not much peer-reviewed research looking at keto versus low-carb as the two diets pertain to fitness performance. Most athletes eat a high-carb diet because carbohydrates are the predominant source of fuel for your body, and your body can turn stored carbohydrates (glycogen) into energy quicker than it can turn fat into energy.
The standard nutritional guidelines for exercise involve eating a high-carb meal or snack before a workout, and following up with another high-carb meal or snack to replenish glycogen stores. However, as long as you give yourself a few weeks to adapt to a keto or low-carb diet, your body will probably perform just fine (provided you eat enough calories overall).
As for building muscle, experts usually recommend a high-carbohydrate, high-protein diet to induce hypertrophy. This tactic has been proven effective over and over again, but newer research suggests that low-carb diets may contribute to favorable body composition changes — that is, more lean body mass and less fat mass.
Summary: Neither low-carb nor keto is ideal for serious athletes, but for people who are looking to improve body composition and casually workout, either diet can support those efforts.
Is Keto or Low-Carb Better for Overall Health?
Doctors and medical dietitians have used the keto diet to treat certain medical conditions for decades. Keto has proven effective at helping patients with epilepsy, seizures, diabetes, metabolic syndrome, and obesity.
But high-fat diets — when they consist of harmful fats — are associated with an increased risk of heart disease, stroke, high triglycerides, and blood vessel diseases. If you choose to go keto, try to fill your plates with as many vegetables as possible and stick to lean sources of protein and healthy fats for the best results.
The keto diet also presents the risk for nutrient deficiencies from lack of food groups (like fruits and starchy vegetables), as well as digestive discomfort from lack of fiber. Again, eat as many non-starchy vegetables as possible, as well as nuts and seeds, to avoid these complications.
Like the keto diet, low-carb diets have also been shown to help with certain medical conditions, including diabetes, metabolic syndrome, and obesity. Low-carb diets are also known to reduce markers of chronic disease, such as high blood pressure, cholesterol, and blood triglycerides.
Unlike the keto diet, though, low-carb diets provide way more wiggle room when it comes to food choices. On the high end, at 150 grams of carbohydrates, you can eat multiple servings of fruit and even small servings of healthy, fibrous foods like oats.
Summary: The keto diet is helpful for some medical conditions but potentially harmful for others, and it presents the risk of nutrient and fiber deficiencies. The low-carb diet allows for more food variety and thus less risk of deficiencies.
So, Should I Go Keto or Low-Carb?
Keto and low-carb diets both have proven health benefits, so deciding which diet to start is really a matter of evaluating your individual goals, needs, and health status. If you’re interested in the concept of ketosis but feel hesitant about such a drastic, sudden reduction in carbs, you might want to start with a low-carb diet and slowly shift to keto. Regardless, this is a decision to be made with the consultation of a healthcare professional.
If you want to lose a lot of weight in a short period of time, sending your body into ketosis is an effective — though not always sustainable — way to do that. Just know that low-carb diet offers the same weight loss benefits. It might take longer to reach your goal weight, but you’re more likely to sustain the weight loss for longer because the diet isn’t as restrictive.
If you have a medical condition that you think would benefit from a keto diet, talk to your healthcare provider or a registered dietitian who specializes in medical nutrition. If you have a medical condition that might be exacerbated by keto, such as high cholesterol or atherosclerosis, definitely talk to your doctor before starting the keto diet.
A low-carb diet is usually a better choice for people who exercise regularly and those who engage in high-intensity exercise such as interval training, CrossFit, or extreme outdoor activities such as rock climbing.
For some, the restrictive eating habits associate with both diets can complicate your relationship with cravings and send you into yo-yo dieting mode, where you lose and regain weight in a vicious cycle. Only careful consideration and thoughtful approach to the facts of both diet can help you determine either’s benefits to you.