How does juicing fit into a healthy diet?
I’ve gotten a lot of questions from listeners about the pros and cons of juicing so today I’ll take a closer look at the claims and give you my take on what juicing can and can’t do for you.
Juicing for Health and Nutrition
Fresh fruit and vegetable juices have a reputation for being super healthy, and it’s true that juices can be a concentrated source of valuable nutrients. As Steph commented in an email, you often hear people say that the nutrients in juice are also easier for your body to absorb than the nutrients in whole fruits and vegetables. And there is some evidence that certain nutrients, especially those in the carotenoid family, seem to be better absorbed from juice.
Carotenoids are found in carrots, of course, but also in tomatoes, spinach, apricots, melons, peppers, and lots of other brightly-colored fruits and vegetables. This class of nutrients seems to play a big role in preventing cancer.
But the nutrients aren’t the only things that are quickly and easily absorbed from juice.
Juice is also a concentrated source of natural sugars. If you consume it without any other food, juice passes relatively quickly through your stomach to your small intestine, where the both the nutrients and the sugar are rapidly absorbed.
Faster Isn’t Always Better
When it comes to sugar, rapid absorption isn’t necessarily a good thing. A big glass of fresh juice can cause a sudden sharp rise in your blood sugar, which in turn provokes a big release of insulin from the pancreas, which then causes a quick drop in blood sugar.
That particular roller coaster is the sort of thing we like to avoid. For one thing, the blood sugar roller coaster isn’t very fun to ride. Your energy levels tend to go up and down with the rise and fall of your blood sugar and you usually end up hungry sooner than you would if you ate foods that are more slowly digested.
For another thing, the blood sugar roller coaster ride is tough on the pancreas. It can even set up a situation where your cells lose their sensitivity to insulin and your pancreas can’t produce enough to get the job done--otherwise known as Type 2 diabetes. I’m not saying that drinking fresh juice will give you diabetes, but the high sugar content is something to be aware of--especially in juices made from carrots, beets, and most fruits.
At the same time, I’m always nagging you to eat more fruits and vegetables and, as Niki points out, fresh juice can be a way to work in more servings than you might otherwise get--or to sneak in some types of nutritious vegetables that you otherwise wouldn’t eat at all. True enough.
As a rule, it takes many servings of fruits and/or vegetables to produce a single serving of juice. So you could theoretically get your entire day’s requirement of vegetables by knocking back a few ounces of juice. But unlike whole fruits and vegetables, juice has no fiber. And one of the ways in which eating more fruits and vegetables improves your health is by increasing your fiber intake; so if you’re leaving all the fiber in the juicer, you’re missing out on that important benefit.