Why Use Whey Protein to Break Your Cleanse Day

Why Use Whey Protein to Break Your Cleanse Day

One of the principal findings of clinical studies around intermittent fasting with Isagenix-style Cleanse Days is that it can be an efficient method to accelerate fat loss and improve health markers (1-3). However, especially for the physically active on a weight-reduction program, a common concern is the decreased intake of calories that could lead to problems with maintaining or building muscle.

Muscle is in a constant state of build up and break down in a process called protein turnover (4;5). Building muscle is controlled largely by a cellular mechanism called mTORC1. How much energy (calories) is consumed and the level of protein intake affect mTORC1 and ultimately the amount of muscle a person has (6;7). Reducing food intake or fasting can potentially reduce mTORC1 signaling and halt muscle building (8).

What may come as a surprise to some is that during times of increased energy demand or reduced food intake, protein requirements are increased above what the Institute of Medicine recommends. In fact, it’s now recommended that physically active individuals eat 1.2 to 1.7 grams of protein per kilogram of bodyweight per day (9). For those who are in an energy deficit and/or are physically active, protein intake above the recommended dietary allowance protects muscle.

It’s no wonder multiple studies have demonstrated that consuming more protein over the recommended dietary allowance (RDA) spares muscle regardless of body size (10-12). When total daily protein intake is in line with the RDA and combined with reduced energy intake, muscle building is blunted even with an optimal serving of high-quality protein like whey (9).

The Protein Solution…

Consuming protein either alone or in a meal promotes a significant increase in building up proteins in muscle (13;14). This is caused by increases in insulin secretion and the amino acids, the building blocks of protein (15;16). To cause the most profound effect on protein synthesis, the protein source should be high in quality, meaning that it contains high levels of branched-chain amino acids, specificallyleucine (17). Lower-quality proteins with lower amounts of leucine may not be as effective (18). Whey is one of the richest sources of leucine, which is the most critical amino acid for muscle synthesis (9).

Moreover, in times of decreased energy and after a fast, eating two to three times the recommended dietary allowance for protein spares muscle and can stimulate muscle synthesis (9). So while taking in the right type of protein is important, so is taking in the right amount.

How To do It

The day after a Cleanse Day should be started with an IsaLean® Shake or an IsaLean® Pro Shake since consuming at least a 20 to 25 gram serving of high-quality protein like whey maximally stimulates muscle synthesis for a few hours (10).

Older individuals should consume more total protein since a higher amount can increase mTORC1 signaling and reduce muscle wasting from age-related anabolic resistance (12). They may have more benefit in using the IsaLean® Pro with a higher protein content. Two shakes and other protein-rich meals should be consumed throughout the day to ensure 1.2 to 1.7 grams of protein per kilogram of body weight per day (9). An example for a 200-pound man and a 150-pound woman would be 154 grams and 115 grams of protein, respectively.

By using these high-quality whey protein products and boosting protein intake, Isagenix customers can enjoy the benefits of improved body composition—as in more lean muscle, less body fat—in addition to all the health benefits of Cleanse Days.


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