The Hidden Dangers of Juicing

Natasha Burton
Green Juice

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Juicing may be the trendy way to supposedly lose weight—and feel great—these days, but drinking your greens might not be all that it’s cracked up to be. In fact, health experts say that juicing can actually do some serious damage to your body, both mentally and physically. So, before you reach for that liquefied kale, heed their advice.

It spikes your blood sugar.
Fruit sugar (fructose) becomes much more concentrated in juice and therefore dramatically elevates the body’s glucose level, known as hyperglycemia. Then, over a relatively short period of time, this leads to an inevitable drop in blood sugar, known as hypoglycemia, according to Kevin Meehan, who has a holistic health and integrative nutrition background as the owner of Teton Valley Health Clinic.

“If this roller coaster ride continues over an extended period of time, then the possibility of a glucose/insulin instability scenario may occur, with the shifts between hyperglycemia and hypoglycemia becoming more dramatic,” he explains.

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It can lead to tooth decay.
Biomimetic dentist Dr. Matthew Nejad, who’s on faculty at USC’s School of Dentistry, says that fruit juices are very high in natural sugars, which can cause as much decay as candy or soda. Both fruit and vegetable juices are also highly acidic, meaning that they can make your teeth more susceptible to erosion and decay, too.

“If you are juicing, make sure you wait at least 30 minutes after finishing your juice to brush your teeth. This allows your mouth to return to its normal pH balance and prevents further damage,” he explains. “It is also recommended to drink juice and other highly acidic drinks through a straw to minimize contact between the juice and enamel.”

It keeps you from chewing.
We take it for granted, but chewing food is actually an important part of our body’s natural function. “Just like any other part of the body, your teeth need blood to flow to help them to stay healthy,” explains kinesiologist Leo Willcocks. “Chewing provides that stimulation, blood flows and your teeth remain stronger. If you’re juicing a lot, then you are chewing even less which equals less blood flow.” In the long term, not chewing enough can actually lead to tooth decay.

Willcocks also mentions that chewing stimulates the digestive tract to prepare it to do its job—not chewing actually causes the digestive tract to be more sluggish.

It alters the pH balance of your stomach.
“When using juice to replace meals, you alter the pH of the stomach and intestine, as well as alter the bile patterns,” says holistic nutritionist Christina Major. “This can lead to undigested whole foods, ulcers, IBS, diverticulitis, leaky gut, and gallstones. We are designed to eat our foods, not drink them.”

She says that when you’re using juicing to supplement a healthy diet, there isn’t a problem. The body enjoys the extra nutrition. But when you’re drinking only pure, clear juice, and get rid of the fibers and starches, they not only risk stomach issues, but they throw away over half of the nutrients and bulk up on sugar. “This is the fast track to nutritional deficiencies and weight gain,” she says.

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It can stress out your body.
If you are juicing as a cleanse, and not as a supplement to eating real food, this massive calorie restricted diet can be the equivalent of short-term starvation, says fitness expert Todd Nief, owner and director of training at South Loop Strength & Conditioning.

“A starvation diet causes a significant stress response in the body and elevates cortisol,” he says. “If you already have excessive stress or poor tolerance to stress, this is going to be the furthest thing from healthy for you.”

It could lead to disordered eating.
Licensed psychologist Alexis Conason, Psy.D., who specializes in the treatment of overeating disorders and body image, worries about the mental dangers that juicing as a dieting measure can cause.

“When we are only drinking juices and not eating any other foods, we are depriving ourselves both physiologically and emotionally,” she explains. “For example, when doing a cleanse, you may feel hungry or crave a certain food but not allow yourself to eat that food because it is prohibited on the cleanse. Ignoring our body’s natural cues of hunger, satiety, and fullness leads to deregulation of our appetitive system and patterns of disordered eating. When we do go off the cleanse, many are prone to overeating. We then believe that the solution to overeating is another cleanse and the cycle of disordered eating begins.”

Wellness coach Kaila Prins, who works with clients on eating disorder recovery and body image, agrees. “Juicing is a huge risk for those who are prone to disordered patterns with food,” she says. “Because juicing is touted by the media as ‘healthy,’ it’s easy for people with a disordered relationship to food to hide behind that label and fool even themselves.”