Is juicing for weight loss healthy?
Juicing has become a popular way for people to lose weight quickly by extracting the nutritious juices from fruits and vegetables. Proponents claim that juicing helps you absorb more nutrients and gives your digestive system a rest. But is juicing truly a healthy, sustainable way to lose weight?
How Juicing Works
Juicing involves extracting the liquid from fruits and vegetables, while removing the solid fiber content. This is typically done using a juicer machine. The resulting juice contains most of the vitamins, minerals and plant chemicals from the produce, but lacks the fiber.
Since juice contains little to no fiber, it can be absorbed very quickly into your bloodstream. This gives you a concentrated dose of nutrients without having to digest the solid food. Many people believe this helps you receive more nutrients from produce.
Juicing advocates also claim that removing fiber makes digestion easier, allowing your system to use its energy for other detoxification processes. However, research shows that fiber is very important for gut health and weight management.
Nutrition in Juice vs Whole Produce
Juicing extracts the juice from fresh fruits or vegetables. This removes most of the fiber, turning it into a liquid concentrate.
Since the skin and seeds from the produce are also removed, some nutrition is lost in the process. For example, about two-thirds of vitamin C is lost from oranges when juiced rather than eaten whole.
Here is a comparison of the nutrients in 8 ounces (240 ml) of orange juice vs one medium orange:1
| Nutrient | Orange Juice (8 oz) | Whole Orange (1 medium) |
|---|---|---|
| Calories | 112 | 69 |
| Carbs | 25 grams | 17 grams |
| Sugar | 21 grams | 14 grams |
| Fiber | 0 grams | 3 grams |
| Vitamin C | 93% DV | 130% DV |
| Potassium | 8% DV | 12% DV |
As you can see, orange juice has more sugar, calories and carbs than the whole fruit, along with no fiber. You also get more vitamin C and potassium from eating the whole orange.
This pattern is similar for other fruits and vegetables as well. Juicing removes healthy fiber and nutrients from the produce.
Weight Loss on a Juice Diet
Juice diets involve getting most of your daily calories from fresh vegetable and fruit juices. They are often very low in calories, protein, fiber and fat.
Some example juice diet plans include:
- Drinking only fresh juices for 3–10 days
- Alternating days of juicing with days of regular healthy meals
- Replacing one or two meals per day with vegetable juices
This approach can help you lose weight quickly in the short-term because you are severely restricting calories. Some juice diets provide less than 700 calories per day.
For example, this 3-day juice diet provides less than 700 calories per day from juices alone:
| Day 1 | Day 2 | Day 3 |
|---|---|---|
| 8 am: 16 oz green juice | 8 am: 16 oz green juice | 8 am: 16 oz green juice |
| 11 am: 16 oz root juice | 11 am: 16 oz root juice | 11 am: 16 oz root juice |
| 2 pm: 16 oz fruit juice | 2 pm: 16 oz fruit juice | 2 pm: 16 oz fruit juice |
| 5 pm: 16 oz veggie juice | 5 pm: 16 oz veggie juice | 5 pm: 16 oz veggie juice |
At only around 600 calories per day, this kind of low-calorie diet will result in fast weight loss in the short-term. However, once you stop the juicing program, the weight will likely return.
Potential Benefits of Juicing
Here are some of the top health benefits claimed by juicing advocates:
- Increased vegetable intake: Juicing makes it easier to consume a lot of produce, packing many servings of vegetables into one glass.
- Higher nutrient absorption: The liquid format may allow for better absorption of some nutrients, especially carotenoids from vegetables.
- Phytonutrient boost: Juices contain high concentrations of plant chemicals called phytonutrients, which have antioxidant and anti-inflammatory benefits.
- Enzyme boost: The enzymes in fresh fruits and vegetables may remain intact in juices to support digestion.
- Blood sugar control: Replacing high-carb meals with low-calorie, low-sugar vegetable juices can help control blood sugar levels.
However, most of these benefits can also be achieved by simply eating more fruits and vegetables as whole foods. Therefore, juicing should not replace healthy whole produce in your diet.
Downsides of Juicing for Weight Loss
Despite its initial popularity, there are some important downsides to juicing that must be considered:
- Lacks fullness: Juice contains little fiber and protein, so it does not fill you up like whole fruits and vegetables do.
- Nutrient loss: Fiber, pulp and skin, which contain nutrients and plant chemicals, are removed during juicing.
- Sugar spikes: Juices can spike blood sugar when consumed in excess, especially fruit juices.
- Tooth decay: The acidity of fruit juices may erode tooth enamel with excessive use.
- Low in protein: Juices lack protein, an essential macronutrient for maintaining muscle mass during weight loss.
- Weight regain: The fast weight loss from juice diets is often unsustainable and is typically followed by weight regain.
- Digestive issues: The sudden increase in fruit and vegetable intake on juice diets may cause gas, bloating and diarrhea.
For these reasons, juice cleanses or detoxes are not scientifically proven weight loss strategies. They should only be followed for brief periods of up to a few days at a time.
Is Juicing Better Than Blending?
Blending, or making smoothies, has the advantage of retaining all parts of the whole produce, including the fiber-rich pulp. This makes smoothies more filling and nutritious than juices.
Whole fruits and veggies also contain beneficial plant chemicals concentrated in the skin. Blending keeps these intact, while juicingremoves them.
For example, this chart compares the nutrients in 8 fluid ounces (240 ml) of blended tomato to juiced tomato:2
| Nutrient | Blended Tomato | Tomato Juice |
|---|---|---|
| Calories | 54 | 31 |
| Carbs | 9 grams | 5 grams |
| Fiber | 2 grams | 1 gram |
| Lycopene | 2,859 mcg | 1,920 mcg |
| Vitamin C | 28 mg | 16 mg |
| Vitamin K | 8 mcg | 6 mcg |
Blending retains more fiber, lycopene, vitamin C and vitamin K than juicing. Similar results have been found for other produce like carrots, oranges and grapes.
Therefore, blending is likely a healthier and more filling option than juicing. Consider opting for smoothies over juices whenever possible while trying to lose weight.
Healthy Juicing Tips
If you do decide to try juicing, here are some tips to make it more nutritious:
- Use mostly vegetables instead of fruit, which is higher in sugar and calories.
- Add ingredients like nuts, seeds, nut butters, protein powder or full-fat yogurt to make juices more balanced and filling.
- Drink juices in moderation by limiting yourself to 8–16 ounces (240–470 ml) per day.
- Aim to eat whole fruits and vegetables as well, not just juice them.
- Be aware that produce oxidizes rapidly after juicing, losing some nutrients. Drink juices as soon as possible.
- If you have diabetes or blood sugar issues, monitor your blood sugar response when adding juices.
- Rinse your mouth after drinking acidic juices, which can erode tooth enamel.
Additionally, make sure to get medical clearance before starting a juicing regimen, especially if you have any underlying health conditions.
The Bottom Line
Juicing can provide a concentrated dose of nutrients from fruits and vegetables. However, the fiber, pulp and skins – which contain nutrients and plant chemicals – are missing from juices.
While juice diets may lead to short-term weight loss, they are likely unsustainable. Replacing whole produce with juice removes fiber and protein, which are important for feeling full.
For health and weight loss, it is better to focus on eating whole fruits and vegetables rather than juicing them. Blending keeps more of the whole food intact, including the fiber.
Overall, juicing should not replace a balanced, healthy diet focused on whole foods. But adding the occasional vegetable juice can provide beneficial plant nutrients.
References
- Atkinson FS, et al. International tables of glycemic index and glycemic load values: 2008. Diabetes Care. 2008 Dec;31(12):2281-3.
- Dias JS, et al. Impact of traditional and innovative processing on bioactive compounds and functionality of tomato juice. Food Chem. 2018 May 1;251:7-13.
