If you’ve been trying to lose weight at any point over the past several years, chances are you’ve heard about or possibly even tried a ketogenic diet. This fat-heavy approach to weight loss has gained a lot of attention in recent years, but it’s not the easiest diet to get quite right.
Originally developed in the 1920s to help children with difficult-to-control epilepsy, the diet eliminates nearly all carbohydrates. This means your body will have to rely on other means of fuel, such as fat and protein.
The classic keto diet “is a high-fat, adequate-protein, low-carbohydrate diet designed to produce ketosis through mimicking the metabolic changes of starvation, forcing the body to use fat as its primary source of energy,” says Cathy Leman, a dietitian, personal trainer, nutrition therapist, speaker, writer and breast cancer survivor based in Chicago.
Helping the Body Achieve Ketosis
When the body relies on fat for fuel, it generates ketone bodies — chemicals manufactured in the liver when fat is metabolized. This process is called ketosis. Getting into and staying in ketosis can be tricky, as it requires just the right ratio of carbs to fats to proteins. That’s where certain substances called exogenous ketogenic supplements — aka keto diet pills — might come into play.
The human body generates ketone bodies naturally — or endogenously in med-speak — when it breaks down fat for fuel. But you can also introduce ketone bodies from an exogeneous — or external — source, which would be an exogenous ketogenetic supplement.
Essentially, exogenous ketone supplements are a pill or powder that contain ketone bodies intended to boost the levels of these substances in the body to facilitate ketosis.
There’s a number of different products on the market that answer to the name of exogenous ketogenic supplement. They usually contain the active ingredient beta-hydroxybutyrate ketone.
The two most common types of keto diet pills are:
— Ketone esters, which are usually sold as a liquid and are used more often in research settings rather than in a consumer product.
— Ketone salts, which are often sold as a powder made from combining ketones with another chemical, such as potassium magnesium, sodium or calcium.
[Read: Keto-Friendly Sweeteners.]
Do Keto Pills Work?
The idea is that these supplements can assist you in getting into ketosis faster — it typically takes from about two days to more than a week to reach that fat-burning state. And once you’re in ketosis, a supplement could help you stay there. Theoretically, this all means you might lose more weight even faster.
The theory makes sense — if you need ketone bodies to achieve ketosis, adding them as a supplement should help you get there more easily. But whether exogenous ketogenic supplements actually work isn’t entirely clear.
Some research, such as this study from 2014, has indicated that adding exogenous ketones can elevate the number of ketones in the body. But whether that means you can achieve ketosis faster or maintain it longer is still inconclusive, according to a 2018 review study.
One of the reasons why supplementation may not be all that effective is because the body seeks to maintain an even level of ketones to prevent a potentially toxic build-up of these chemicals in the bloodstream. When the body senses that ketone levels are high, the liver stops making its own, so supplementing ketones might actually cause your body to stop producing them. This could in turn actually limit your ability to stay in that target ketogenic, fat-burning zone that’s been associated with rapid weight loss.
And while there’s some indication that the keto diet itself is effective for weight loss, there’s little in the way of long-term research as to how it impacts the body and whether the weight loss you might achieve is durable, says Monica Chan, supervising dietitian with Riverside University Health System in California. “Studies suggest that weight loss related to the keto diet is likely due to a reduction in hunger levels, water weight loss and a calorie deficit.”
She notes that “following the ketogenic diet has been linked to decreased levels of ghrelin, one of your body’s main hunger hormones,” which may make it easier to avoid overconsumption of calories.
However, significantly reducing carbohydrate intake can lead to a loss of water because carbs hold water when stored in your body. “When you reduce your carb intakes, such as during the initiation phase of the keto diet, stored carbs are released along with additional fluid, resulting in weight loss of varying amounts.”
This is problematic because when you come off a keto diet, your consumption of carbohydrates will increase and that means your body will hang onto more water and some of that weight loss with be reversed in short order.
For many people, maintaining a keto lifestyle is difficult, as the menu is very restrictive, so it’s common to come off the diet and regain weight, regardless of whether you’re using a supplement or not.
[READ: Does Keto Cause Menopause?]
If you’re planning to use a keto diet pill or powder, be sure to do your homework first.
First, Chan recommends checking with your doctor before you start a keto diet itself, as this approach to weight loss is not for everyone. “You should have your physician check your blood work to ensure you’re appropriate for this extremely low carbohydrate diet,” she says.
And keep in touch with your doctor to ensure that you’re staying healthy while following the plan. “Continue to have your physician check your blood work closely to make sure your blood glucose levels, liver and kidney functions are at target,” she says.
If you want to add a supplement for weight loss — or any other reason – be sure to speak with your doctor first. There’s always the possibility that a nutritional supplement will interact negatively with another medication you’re taking or cause other unintended side effects. Be sure to discuss everything that you take, whether it’s a prescription or an over-the-counter medication, with your health care provider.
Also, beware some of these products can be very expensive. And some companies may enroll you in an autorenewal plan where you automatically get charged for a new shipment of pills each month without your realizing it. These plans can be difficult to cancel sometimes and may be more costly than you expected. As such, you may end up paying a lot of money for a product that doesn’t contain what it says it does on the label.
Dietary supplement products are not regulated by the Food and Drug Administration, so it can be difficult to know whether you’re getting what you pay for. Ask the company to provide its research or evidence that it does what they’re saying it does. A reputable manufacturer should be able to provide information about how its product has been tested and what it contains.
There’s an additional risk of scams with some of these products. Specifically, be wary of supplements being pushed heavily on social media. In July 2020, AARP reported that two women in their 80s had been scammed out of more than $200 each when they purchased keto diet pills, and that the number of reported scams is on the rise.
To protect yourself, be very wary of any supplements being pushed via email or pop-up ad — these points of contact are more likely to lead to a scam product. Also keep an eye out for warning words and phrases in any marketing text, such as “quick-fix,” “guaranteed results” and “scientific breakthrough.” They’re usually a red-flag that the product is making claims it’s unlikely to be able to follow up on.
Alas, there are few short-cuts to healthy and sustainable weight loss, and using a supplement to speed up the process could mean you end up dropping more dollars than pounds.
“Nutritional goals are, and will always be, about the work you put in, and all diets will reach a plateau whether it’s in weight loss, or from being tired of the taste or even just eating certain foods for the diet,” Chan says.
Instead, “the best thing you can do is to focus on healthy eating habits for a lifetime,” as eating healthy and staying active are the keys in weight management.”
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