Have you noticed your Facebook feed flooded with enthusiastic updates from friends jumping on the juicing bandwagon? Juicing has gone mainstream, and many are tempted to give the trend a try. After all, devotees rave about their smaller waistlines, improved mental focus, and glowing skin–and credit the liquid nutritional movement that’s launching multimillion dollar companies.
But is drinking all your nutrients really good for your health? And will a diet rooted in blended fruits and vegetables truly deliver all the benefits proponents claim? Here’s a look at some basic facts about juicing, along with some practical advice from One Medical Group nutritionist Karyn Duggan.
What is juicing?
Many people use the term “juicing” interchangeably with “cleansing” or “fasting.” It’s a diet restricted to fruit and vegetable juices, plus water, and it can last anywhere from a few days to several weeks.
Juice diets typically consist of unpasteurized, “cold-pressed” juices. Whereas store-bought varieties are usually pasteurized (heated then cooled) to prevent spoilage, cold-pressed juices are made by pressing produce between plates to extract fresh liquid, thus avoiding any heat, which advocates claim depletes nutrients. In addition, the juices you’ll find in grocery store refrigerators often contain preservatives and sometimes added sugar.
Why do people do juice fasts?
Ask a group of avid juicers why they juice, and you’ll likely get a variety of answers. Juice companies and devotees claim a diet of liquified fruits and veggies can do everything from improving immune system functioning to eliminating “toxins” to increasing energy. Some juice fans say subsisting on juice alone improves their mental clarity, while others believe the liquid diet will help them shed pounds.
What are the potential health benefits?
Joining the juice movement may have its advantages. Most notably, if you can’t stand the thought of snacking on kale or carrots, juicing can be an effective way to sneak more plant-based foods into your diet. It’s no secret that fruits and vegetables can help prevent everything from obesity to heart disease to stroke, but most Americans don’t consume anything close to the recommended five to 13 servings per day (in fact, the average American gets just three).
What juicing health claims are controversial?
Advocates claim the body better absorbs vitamins and minerals from juice rather than whole foods because juicing gives the body “a rest” from processing fiber. Critics disagree, saying the body not only doesn’t require a digestive break, but that processing the produce in any way–such as juicing a fruit or vegetable rather than eating it whole–actually diminishes its nutritional value.
And regarding that “detoxification” claim–clinical evidence hasn’t demonstrated that cleanses of any kind “detox” the body. The liver, kidneys, and intestines filter toxins naturally through urine, bowel movements, breath, and sweat.
Perhaps the most polarizing point of debate is whether juicing reduces cancer risk. Proponents say the concentration of antioxidants is especially protective against certain cancers, and while it is true that plant-based diets have been shown to reduce cancer risk, there isn’t much research dedicated specifically to juicing.
What are the potential risks and drawbacks?
One thing die-hard juice fans may not admit is that they’re hungry: The lack of fiber makes juice less satiating than whole food.
The biggest issue many people have with juices is that even the unpasteurized, cold-pressed varieties can be high in calories and sugar. “I urge people to be cautious with juice and double-check the amount of sugar on the label,” Duggan says. And if the juice you’re drinking comes without a label, continues Duggan, pay attention to how it’s being made. “To minimize the high sugar risk, make sure the juice you’re consuming includes the least amount of fruit possible, like half an apple or pear. Better yet, rely on lemons or limes to cut the flavor of the greens, and ideally consume your juice after a workout rather than as part of a sedentary lifestyle.”
Who shouldn’t juice?
If you have diabetes, juicing is out of the question–the high sugar content can wreak havoc on your blood glucose levels, and in extreme cases, lead to complications like nerve damage or infections. The American Diabetes Association, however, does recommend three to five servings of non-starchy vegetables a day, and suggests low-sodium vegetable juice as an alternative to more sugary beverages.
If you have kidney disease, excessive juice consumption can also be dangerous. The high levels of potassium and minerals can build up to hazardous levels in the bloodstream, and cause effects like nausea and weakness, and more serious consequences like heart failure in people with advanced-stage chronic kidney disease.
Finally, it’s important to know that certain common medications (including statins, some anti-anxiety pills, and some antihistamines) don’t mix well with certain juices. Grapefruit juice in particular can cause adverse effects by interfering with the enzymes that regulate how a drug is processed by your body.
So, should you juice?
Despite not necessarily living up to all of the purported claims, juicing can be a helpful way to shift away from bad habits like excessive caffeine or alcohol consumption. Additionally, it can help kick-start a healthier lifestyle or motivate better behaviors once the fast is over. But a juice cleanse isn’t a surefire solution for long-term weight loss, and there isn’t enough evidence to consider it an effective method for “detoxing.”
“It can be difficult to eat as many vegetables in a day as we can get in a juice, so juicing can be a reasonable way of achieving that,” Duggan says. “But a juice shouldn’t be a meal replacement. Instead, think of it as a way to amp up the level of nutrients in the diet.”
Whether you plan to sip juice between meals, or you’re sure that a juice fast is your key to better health, it’s important to be informed about what you’re consuming. “Be cautious, use your best judgment, and be savvy about sugar,” Duggan says. “And be realistic about what to expect. I strongly encourage people to have a discussion with a professional who is well-versed in nutrition to help with their ‘cleanse’ and make sure it truly is healing.”
The One Medical blog is published by One Medical, an innovative primary care practice with offices in Boston, Chicago, Los Angeles, New York, Phoenix, the San Francisco Bay Area, Seattle, and Washington, DC.
Any general advice posted on our blog, website, or app is for informational purposes only and is not intended to replace or substitute for any medical or other advice. The One Medical Group entities and 1Life Healthcare, Inc. make no representations or warranties and expressly disclaim any and all liability concerning any treatment, action by, or effect on any person following the general information offered or provided within or through the blog, website, or app. If you have specific concerns or a situation arises in which you require medical advice, you should consult with an appropriately trained and qualified medical services provider.