Fad diets
Juicing
Juice diets have been made increasing popular in the early 2010s with celebrities such as Gwenyth Paltrow and even Dr. Oz creating and promoting certain brands and sharing recipes. It continues to be popular among various celebrities, influencers, and day time television "doctors". "Juicing” or a “juice cleanse" is used to describe a usual 2- 60 day diet that consists of only consuming fruit and vegetable juices. The goal of this diet is to dramatically decrease the intake of calories in order to lose weight. Another thought beghind this diet is that while only drinking fruit and vegetable juice the body will flush out toxins from previous bad eating habits, while replenishing itself with nutrients. This diet is sometimes accompanied by the use of laxatives, exercise, supplements, and sometimes even a sauna to get rid of excess water weight. There are countless juicing diets and recipes that highlight specific vegetables, fruits, and supplements.
Claims
Juicing claims to help with:
-
Losing weight
-
Flushing out toxins
-
Increase Energy
-
Increase Nutrients and Vitamins
Truth to Claims
Losing Weight
This is True.
The goal of this diet is to reduce and restrict one's caloric intake in order to create a calorie deficit. Due to this deficit, one will usually lose weight. This is also usually coupled with laxatives to help maintain this deficit throughout the diet.
Keeping the weight off however, is another story.
Flush out Toxins
Not enough evidence.
A large appeal to this diet is that it claims to detoxify the body of toxins and other harmful substances. However, there is not enough data to support the idea that juicing "detoxes" the body or evidence on detoxing agents themselves.
Increase Energy
Not enough evidence.
Another large appeal to doing a "juice cleanse" is that it is supposed to promote natural energy instead of relying on caffeine such as coffee. There is not enough data to support the idea that a juice cleanse will increase one's energy.
Increase Nutrients/Vitamins
This is True.
This diet consists of mainly fruit/ vegetable juice, so the amount of nutrients they will receive might be higher than usual. However, the nutritional value would be the same in a physical state with other food (Hyson,2015). However, drinking only vegetable and fruit juice leaves behind other important food groups and deprives the body of fiber. Fruit, although nutrient heavy, also contains a large amount of sugar. Drinking 8 servings of fruit juice risks eating more sugar than expected.
Danger in Juice?
Although, there are no adverse outcomes related to bodyweight, plasma lipids, and blood glucose in adults and children from pure fruit juice (Hyson, 2015).
A variety of fruits and vegetables are recommended to be turned into juice in order to have various amounts and types of vitamins and nutrients. However, there are staple vegetables that are used like beets, spinach, celery, apples, kale, as well as soy products that are used in many if not all juice cleanses. Most of these are high in oxalate, which studies have found can be a cause of oxalate neuropathy leading to acute kidney injuries (Getting, Gregoire, Phul, & Kasten, 2013). Oxalate neuropathy is characterized by calcium deposits in the kidney which can affect the filtering of urine.
Oxalate Rich Foods
-Beetroot
-Beet leaves
-Kiwi
-Collards
-Spinach
-Soy products
-Star fruit
-Leak
-Okra
Low Calories High Stress
Restricting caloric intake increases cortisol levels in the body(Tomiyama, Mann, Vinas, Hunger, Dejager, & Taylor, 2010). Extremely low calorie diets increase the body's cortisol levels, possibly leading to negative effects. These effects include rebounding the weight by binge eating. The high levels of cortisol that result from dieting could be the reason behind the high failure rate of diets.
Possible Benefits
Convenience
-
Juicing is a convenient way to get the recommended servings of vegetables and fruit.
Nutrient Intake
-
Many Americans do not have enough fruits and vegetables in their diet. Juicing is a way to increase the intake of the nutrients in these foods.