I’m constantly asked about diets. One that pops up from time to time, called Isagenix, markets itself as a solution for weight loss, as well as a booster of performance, vitality, and well-being. The products are sold through the Isagenix website, Amazon, and directly by salespeople. Here’s what you need to know about the brand, its health implications, and whether it can really help you lose weight.
What is Isagenix?
Isagenix offers a number of weight-loss options, from the Weight Loss Basic Pack (a 30-day system) to the 9-Day System, which includes IsaLean® Shake powder and a cleanse. According to a video on the brand’s website, the shakes can support weight loss when used as a meal replacement for one or two meals daily. The other meals should be balanced and limited to 400-600 calories, bringing the total to roughly 1,000 to 1,400 calories per day.
The traditional version of the shake is dairy-based, made with whey protein. The company now offers a plant-based option, too, made from pea and brown rice proteins. Two scoops of the shake powder mixed with water provide 240 calories plus 5-6 grams of fat, 24 carb grams (including 8 grams of fiber), and 24 grams of protein. It also contains digestive enzymes and a number of vitamins and minerals, like zinc, calcium, vitamin D, magnesium, and iron.
I’m not crazy about the stevia used to sweeten the powder. In my experience, its intense sweetness may stoke a sweet tooth or disrupt appetite regulation. I also have concerns about stevia's potential impact on healthful gut bacteria. I do, however, like the comprehensive nutrients provided per serving and macro balance (which is the ratio of protein, carbs, and fat).
Can Isogenix promote weight loss?
Among my clients, I’ve seen that replacing a meal or two with a balanced shake or smoothie can be a helpful short-term strategy for curbing calories and shedding pounds. But I have a number of questions about other products offered in the Isagenix plans. These include cleanses, energy shots, an accelerator designed to rev metabolism and burn fat, and snacks of chewable wafers made from milk powder and ingredients like hemp, sunflower, and flax. (Why not just eat an ounce of seeds?)
Also, the products are pricey. The 9-Day System costs $207.94 and the 30-Day Premium Pack will set you back $588.93.
What the science says
While the products have been used in some published research, the results aren’t long-term (for example, they don't measure weight maintenance five years out). One study involved intermittent fasting and another only included 24 subjects. Plus, the studies were funded by the brand. In my opinion, this is scant support.
I’m also quite skeptical about some of the Isagenix products and approaches, specifically the cleanse. The cleanse option severely limits calories, and it contains aloe vera, which may have a laxative effect. Isagenix promotes the inclusion of additional beneficial ingredients, such as turmeric, berry extract, and ashwagandha, an herb touted as an adaptogen (a natural ingredient that helps the body adapt to stress or counter the harmful effects of stress).
However, the products also claim benefits that include the release of fat-soluble toxins, as well as support for immune function, mental clarity, cellular health and energy levels, and metabolic support—all without studies specifically on the cleanse itself. I find that disappointing, particularly for a company that states, “Transparency and accuracy are a top priority.”
Should you try Isagenix?
Bottom line: my biggest concerns about Isagenix are the cost, stick-with-it-ness factor, and the questionable nature of products like the cleanse and so-called fat-burning accelerator. If you feel you need a jump start, there are plenty of clean ingredient, plant-based, and even organic protein powders or pre-made shakes available that aren’t bundled with other supplements you really don’t need.
In all my years counseling clients, I have found that cleanses typically backfire. The quick weight loss is primarily water. And in many cases, all of the pounds lost, or all—plus more—are regained. Finally, what truly works for losing weight and keeping it off long-term is a collection of healthy habits you can put into action and maintain, something that comes from your mind-set, not a box full of products.
Cynthia Sass, MPH, RD, is Health's contributing nutrition editor, a New York Times best-selling author, and a consultant for the New York Yankees.
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