A Recent Study Debunks the Myth of Healthy Juices

Watan-In recent years, there has been a surge in promoting juice consumption as a method to intake fruits and vegetables, along with marketing diets that rely solely on juices, claiming to improve health, aid in weight loss, and detoxify the digestive system.

However, a study published in the journal “Nutrients” in late January warned that “the absence of most insoluble fibers in juice may reduce the health benefits of whole fruits and vegetables. It may also lead to negative shifts in gut and oral bacteria associated with inflammation, affecting metabolism, immunity, and mental health.” The study further indicated that relying exclusively on juice for detoxification “could harm health within three days.”

While juicing fruits and vegetables is a common and convenient way to obtain nutrients, experts state that “juice alone is not sufficient to replace a balanced diet.” This is especially pertinent in light of new research revealing that “juice may not be worth the squeeze,” as noted by Sarah Garone, a certified nutritionist and health and wellness writer for “Health.” She explained that “even before this study was published, many experts warned that juice’s reputation as a detox or weight loss tool exceeds its actual health benefits.”

Consequences of Sacrificing Fiber

According to the American “Wyoming News” network, the study conducted by researchers at Northwestern University in Illinois involved three groups of healthy adults. One group consumed “juice only,” the second group consumed “juice with whole foods,” and the third group consumed “whole plant-based foods only.”

The research team found that the first group, which consumed only juice, showed the greatest increase in gut bacteria associated with inflammation. In contrast, the last group, which consumed “whole plant-based foods,” experienced healthier microbial changes. The middle group, which consumed “juice along with food,” exhibited some bacterial shifts, but they were less pronounced than those in the juice-only group.

The researchers stated that their findings suggest that “juice without fiber may disrupt the microbiome or beneficial bacteria, leading to long-term health consequences.”

Impact of Juice on Children

Dr. Melinda Ring, a professor at Northwestern University Feinberg School of Medicine and the principal investigator of the study, stated, “Most people believe that juice is a healthy detox for the body, but consuming it in large quantities with little fiber can lead to microbial imbalances that cause negative consequences such as inflammation and impaired gut health.”

She explained that “juicing removes much of the fiber found in whole fruits and vegetables, which feeds beneficial bacteria that produce anti-inflammatory compounds.” She added that “the high sugar content in juice feeds sugar-loving harmful bacteria more, negatively affecting gut and saliva microbes.”

The research team also found that the oral microbiome showed “dramatic” changes during a juice-only diet, characterized by “a decrease in beneficial bacteria and an increase in bacterial groups associated with inflammation.” Ring noted that “this clearly demonstrates how quickly juice and fiber-free diets can impact the microbiome and bacterial groups associated with health, especially in children, who often consume juice as a substitute for fruit.”

She recommended that juice enthusiasts ensure they “maintain intact fiber or consume juices with whole foods to balance the impact on the oral and gut microbiome.”

Five Outcomes of Excessive Juice Consumption

“While relying on juice may seem beneficial in theory for those who find it difficult to consume enough fruits and vegetables,” says Amanda Beaver, a health nutritionist at “Houston Methodist,” she clarifies that juicing fruits and vegetables may lead to the following:

• Loss of Vital Nutrients: Juicing can result in the loss of essential nutrients, making the juice almost entirely devoid of protein, healthy fats, and certain vitamins like B12.

• Removal of Fiber: Fiber is crucial for “feeding” healthy bacteria in our gut, helping us feel full, preventing rapid blood sugar spikes, and preventing constipation. According to Amy Moyer, a nutritionist at the University of North Carolina, “juicing can lead to a loss of about 90% of the fiber, while simultaneously effectively increasing sugar and carbohydrate content.”

• Unwanted Side Effects: The low-calorie content in most juices can lead to fatigue, headaches, intense food cravings, and dizziness.

• Impact on Muscles and Bones: Due to the lower protein content in juice, it may lead to a loss of muscle and bone strength.

• Burden on the Kidneys: Beaver warns those with kidney issues against “excessive juicing,” as some juices contain high levels of oxalate salts, which can cause kidney stones.

The Myth of Weight Loss

Excessive juice consumption may lead to some weight loss in the short term, “but this doesn’t mean it’s a healthy way to lose weight, nor is the loss sustainable,” says Beaver. She explains that the weight loss observed doesn’t mean any fat has been lost; “it’s often due to the lack of food in the digestive system and muscle loss as the body relies on juice.”

More surprisingly, muscle loss slows down metabolism, which may contribute to weight gain once regular eating resumes, “with the potential to suffer from the negatives of slow metabolism and affected bone strength.”

Enjoy Whole Fruits and Vegetables

While juice can be a good way to stay hydrated and obtain some vitamins and minerals, nutritionist Lisa Frousting emphasizes that incorporating it alongside plenty of fiber and other nutrients throughout the day is the best option. She attributes the popularity of juice to being “heavily influenced by celebrities, social media, friends, and family.”

Beaver also recommends “eating whole fruits or vegetables with a source of protein like Greek yogurt or milk, instead of juicing them,” considering it the best way to obtain the potential benefits of juice, along with natural fiber, and to feel full longer after meals.

She asserts that “although juices themselves may be healthy, they are not nutritionally balanced and should not be used as meal replacements.” It’s better to enjoy whole fruits and vegetables as part of your meals and snacks.