Traditionally juice diets have been used for detoxification purposes. The principles behind this are straightforward and do make sense, but are only designed for a short period of 2-3 days maximum (often called a juice fast).
By only consuming fresh juices for a period of time you naturally abstain from fats, processed carbohydrates and refined sugars as well as substances like coffee and alcohol.
As a result, this is extremely beneficial for cleansing the liver and kidneys and their related systems, including the whole digestive tract. It is believed too that by giving the digestive system a 'rest' from fiber; digestion is easier, and nutrients are able to be absorbed more efficiently.
Recently many bold claims have been made about prolonged juice fasting, such as disease fighting, free radical destroying, fat burning and pain alleviating results. However, many of these claims are as yet to be supported by any reliable research.
Juice Fasting is Not a Long-term Solution to Weight Loss
Juice fasting exclusively as a weight loss measure is a short-term solution for a long term problem that can in some situations result in unwanted complications.
The term 'juicing' pretty much means drinking your food, primarily fruits, vegetables and herbs. Incorporated into a healthy diet juicing is a great way to boost energy levels and consume extra nutrients - a popular favorite is beetroot, celery, carrot, apple, ginger and mint; perfect for a morning 'pick me up'.
Weight will certainly be lost when 'juicing' however it is not guaranteed that any actual fat will be burnt. Instead you even risk losing muscle mass due to the absence of protein in the diet. You also run the risk of slowing your metabolism, meaning when you resume a normal diet, less energy will be burnt and potentially more fat will be stored immediately following the 'juice fasting' period.
These problems may be combatted by consuming juice more frequently (every 2-3 hours) and balancing your juices by adding protein, either in the form of powder supplements or natural sources such as almond milk or Greek yogurt.
High-carb and High-calorie
Juices can also be surprisingly calorie dense, especially when predominantly fruit. This is due to their high carbohydrate content. The actual process of juicing fruit and vegetables can also remove some of their natural benefits; of particular concern is the absence of fiber. Once the physical bulk, largely fiber, is removed, the remaining sugars form a much larger percentage of what remains.
If viewed as a short-term revitalizing and cleansing fast, juicing can be an extremely positive part of a healthy lifestyle, especially when combined with a balanced diet and regular physical exercise. As a long-term weight loss solution, however, it is a fad diet that cannot and should not be sustained for long periods.
Initial dramatic weight loss may indeed occur, however little will be done for long-term weight maintenance.
If you do decide to try a juice fast you should consult your healthcare professional first and discuss any individual potential risks. Juicing is not recommended for people suffering diabetes and heart disease nor is it suitable for pregnant or breastfeeding women.
Always include a wide selection of fruits and vegetables, washed thoroughly before use and where possible choose organic produce to eliminate concentrated consumption of pesticides, herbicides and fertilizers (particularly in leafy greens).