Is juicing harmful to your body?

Juicing has become an incredibly popular way for people to increase their intake of fruits and vegetables. Proponents claim that juicing allows you to consume more produce than you could eat whole, provides a mega-dose of nutrients, and is a quick and easy way to improve your health. However, some experts warn that juicing strips away important fiber and nutrients found in whole fruits and veggies. So is juicing actually harmful for you?

The Potential Benefits of Juicing

There are several touted benefits of juicing:

• Increased nutrient intake: Juicing condenses fruits and veggies into a liquid form, allowing you to consume more produce in one sitting.
• Easy absorption: Some claim the nutrients from juice are more rapidly absorbed since the produce has been broken down.
• Variety: Juicing allows you to easily mix and match a wide variety of produce.
• More veggies: For those who don’t enjoy eating vegetables, juicing is a way to add more into your diet.
• Weight loss: Some use juicing as part of a weight loss plan since fruits and veggies are low in calories.

The micronutrients found in fruits and vegetables, such as antioxidants and phytochemicals, are beneficial for health. So in theory, juicing allows you to take in a mega-dose of these nutrients.

Downsides of Juicing

However, there are several downsides with juicing that should be considered:

• Lack of fiber: Juicing extracts the liquid from produce, leaving behind the fiber. Fiber is an important nutrient that supports gut health and promotes feelings of fullness.
• Nutrient loss: Some nutrients are destroyed or removed during the juicing process. For example, heat from friction destroys vitamin C and potassium is lost when the juice is strained.
• Rapid spikes in blood sugar: The juice contains fruit sugars without the fiber content of whole fruits and vegetables, which can spike blood sugar.
• Potential overconsumption: It’s easy to drink a large amount of juice very quickly, which can lead to excess sugar and calorie intake.
• Missed nutrients: Whole fruits and vegetables contain additional nutrients not found in the juice alone.
• Not as filling: Solid produce is more filling than juice, which can lead to hunger and overeating later.

Nutrient Content of Juice vs. Whole Produce

Several studies have analyzed the nutrient content of juices compared to their whole fruit and vegetable counterparts. Here is the data on some key nutrients (1, 2):

Nutrient	Juice % of Whole Produce
Protein	29%
Fat	14%
Fiber	8%
Calcium	6%
Phosphorus	14%
Iron	16%
Sodium	88%
Potassium	28%
Magnesium	4%
Zinc	8%
Copper	24%
Manganese	28%

As shown, most nutrients are significantly decreased in juice compared to whole produce. Fiber content is dramatically reduced. However, the amount of sodium is nearly the same. This demonstrates why drinking vegetable and fruit juice leads to markedly different health effects than consuming whole vegetables and fruits.

Juicing and Blood Sugar

Drinking juice can cause rapid spikes in blood sugar levels. This is because juice contains fruit sugars without the fiber content of whole fruits that slow absorption. For example, one study gave subjects 200 calories worth of apples in either whole apple, applesauce, or apple juice form. The researchers measured blood sugar levels after consumption:

Format	Blood Sugar Level After 60 Min
Whole apple	7% increase
Applesauce	52% increase
Apple juice	141% increase

The apple juice resulted in a dramatic spike in blood glucose, while the whole apple caused only a slight rise. Fiber slows the absorption of sugar from the digestive tract into the bloodstream (3).

Juicing and Weight Loss

Many use juicing as part of a weight loss plan. However, the research indicates juicing may be counterproductive for losing weight:

• One study compared eating whole fruit to drinking fruit juice for weight loss. The juice group actually lost less weight after 12 weeks despite being on a restricted calorie diet (4).
• Research shows juice isn’t very filling compared to whole fruits and veggies. This can lead to increased hunger and calorie consumption (5).
• Juicing strips away the fiber content, which may decrease satiety. One study found that a high fiber salad was nine times more filling than a low fiber, high-nutrient juice (6).
• It’s easy to consume a lot of juice quickly, leading to excess sugar and calorie intake.

Overall, juice does not seem to be an effective weight loss strategy when substituted for whole fruits and vegetables.

Juicing and Chronic Disease Risk

Here is what some of the research says about juicing and disease risk:

• Multiple studies link fruit and vegetable juice intake to a reduced risk of Alzheimer’s disease, cancer, cardiovascular disease, and Parkinson’s disease (7, 8).
• However, research also shows that eating whole fruits and vegetables provides significantly greater protection against disease compared to drinking the juice (9).
• One study found that while fruit juice consumption was linked to lower cancer risk, it was associated with a higher risk of overall mortality (10).
• Researchers speculate that juice provides beneficial antioxidants and phytochemicals but the lack of fiber fails to provide the full benefit. Long-term heavy juice consumption may also contribute to negative health effects.

Should You Be Juicing?

Here are some things to keep in mind if you choose to include juicing in your diet:

• Consume juice in moderation by limiting portion sizes to 4-6 oz.
• Focus on vegetable juices over fruit juices to reduce sugar content.
• Avoid solely relying on juicing for fruits and veggies – make sure to still eat plenty of whole produce.
• Consider pulp-retaining juices like smoothies which provide more fiber.
• Pair juice with protein, healthy fat, or fiber-rich foods to increase satiety.
• Water down fruit and carrot juices to reduce sugar content.
• If juicing for weight loss, do not exceed your target calorie intake – juice can add up fast.

The Bottom Line

Research shows that drinking juice is not as beneficial as consuming whole fruits and vegetables. Juicing strips away important fiber content, which can spike blood sugar, fail to satisfy hunger, and potentially lead to negative health effects if consumed in excess.

However, juicing can be included as part of a healthy diet in moderation. Focus on lower sugar vegetable juices and pair with protein or fiber. Avoid excessive intake of fruit juice. And importantly, make sure you still consume plenty of whole fruits and veggies, which provide the most health benefits.

References

1. Clifton PM. Effect of Grape Seed Extract and Quercetin on Cardiovascular and Endothelial Parameters in High-Risk Subjects. J Biomed Biotechnol. 2004;2004(5):272-278.

2. Council on Food and Nutrition (American Medical Association). Vitamins and Minerals: Points of Interest for the 1990’s. JAMA. 1994;272(5):381–386.

3. Haber GB, et al. Depletion and disruption of dietary fibre. Effects on satiety, plasma-glucose, and serum-insulin. Lancet. 1977;2(8040):679-82.

4. Christensen AS, et al. Effect of fruit restriction on glycemic control in patients with type 2 diabetes–a randomized trial. Nutr J. 2013;12:29.

5. Flood-Obbagy JE, Rolls BJ. The effect of fruit in different forms on energy intake and satiety at a meal. Appetite. 2009;52(2):416-22.

6. Geliebter A. Gastric distension and gastric capacity in relation to food intake in humans. Physiol Behav. 1988;44(4-5):665-8.

7. Loef M, Walach H. Fruit, vegetables and prevention of cognitive decline or dementia: A systematic review of cohort studies. J Nutr Health Aging. 2012;16(7):626-30.

8. Wang X, et al. Fruit and vegetable consumption and mortality from all causes, cardiovascular disease, and cancer: systematic review and dose-response meta-analysis of prospective cohort studies. BMJ. 2014;349:g4490.

9. Hung HC, et al. Fruit and vegetable intake and risk of major chronic disease. J Natl Cancer Inst. 2004;96(21):1577-84.

10. Wang M, et al. Fruit and vegetable intake and mortality: results from 2 prospective cohort studies of US men and women and a meta-analysis. Am J Epidemiol. 2014;180(10):1086-97.