Dr. Oz Sells Lemons

FacebookTwitterEmail

Photo by Markus Spiske

With his enthusiastic hype and on-air shenanigans, Dr. Oz has always impressed me as sounding more like a used car salesman than a respected cardiothoracic surgeon. A used car salesman may tell you the car is in pristine condition, was always kept in a heated garage, and was only driven round the block once by a ninety-year-old great-grandmother. Then you find out it makes strange rattling noises, and you get a CarFax report that says it was extensively rebuilt after being nearly totaled two years ago in a collision with a cement truck. The used car salesman has lied to you and sold you a lemon.

Dr. Oz promotes all kinds of questionable health claims. He keeps coming up with the next Miracle Weight Loss product, always supposedly better than the one he promoted last month. He has guests who provide testimonials. He may do a half-assed demonstration that proves nothing. He may interview an expert who explains the “science” behind the product. Then you try it and it doesn’t work. Then you look for the scientific studies that supposedly proved it works, and you discover that, as Gertrude Stein said of Oakland, “there’s no there there.” Like the used car salesman, Dr. Oz has sold you a lemon.

So I was not at all surprised to learn that Dr. Oz is selling the other kind of lemon, the kind that grows on trees. No, he hasn’t opened a produce stand or a grocery store, but he is selling the idea that drinking the juice of fresh lemons in water is beneficial to health. His online article is titled “5 Benefits of Drinking Lemon Water: Drinking this delicious beverage is a simple way to improve health.”

The Video

An embedded video clip from his TV show is big on showmanship but short on science. In it, Oz says if you want to shed some unwanted pounds, look and eat a little bit better, “clean eating” may be the way to go. He interviews a nutritionist who offers “a sneaky way to help you eat clean all day long.” She says:

  • You want to avoid chemical preservatives, sweeteners, and artificial colors. You want to eat food “in its truest form,” in its most natural state. (The “natural” fallacy.Sometimes cooked foods are more nutritious.)
  • She says, “after a long night, you want to get hydrated.” (Is there any evidence that you are dehydrated when you wake up?)
  • Having a cup of water with a squeeze of lemon “is a great way to get hydrated.” (Drinking plain water or any other liquid is just as good a way to get hydrated.)

At this point, Dr. Oz chips in and says it increases saliva (wouldn’t that tend to dehydrate you?) but says it is also “thought of as a detoxing way.” (What do you suppose that means? It’s not even good grammar. And the idea that we need to detox is a myth.)

Back to the Article

Making your own lemon juice with fresh lemons is “a simple and refreshing way to sustain a healthy lifestyle. The fruit contains nutrients that are vital to your health. By indulging in a tasty, low-calorie beverage, you will be getting hydrated and reaping five benefits at the same time.”

Let’s examine those five benefits:

  1. Improves skin quality. Collagen helps sustain skin elasticity. “When you increase your intake of vitamin C, you are giving your body the proper nutrients needed to maintain healthy skin.” (But if you don’t have a vitamin C deficiency, you don’t need to increase your intake. And there is no evidence that drinking lemon water has any measurable impact on skin health.)
  2. Aids in digestion. 
    • Starting the day with warm lemon water will “activate your digestive system.” (News flash: your digestive system is always ready to work; it doesn’t need to be activated.)
    • “The citric acid found in lemons supplements your natural stomach acids which help break down food.” (Your stomach doesn’t need any help; it’s already more acidic than lemon juice, and much more acidic than lemon diluted with pH neutral water.)
    • Sipping on this warm beverage also acts as a gentle laxative, promoting regularity. (Eating anything or drinking any warm beverage stimulates a gastrocolic reflex that produces intestinal contractions.)
  3. Supports the immune system. “Increasing your intake of vitamin C will help you gain and sustain your immunity which will ultimately prevent you from getting sick.” (Adequate vitamin C intake does help maintain a healthy body; but no, supplemental vitamin C does notprevent you from getting sick. In fact, the immune system may make you sick with autoimmune diseases.)
  4. Prevents kidney stones. Lemons contain citric acid; low citrate levels may play a role in the formation of calcium-based kidney stones. “Although it is not proven,it seems that lemon products increase urinary citrate levels.” (This is pure speculation. Lemon water might reduce the risk of kidney stones, but there’s no evidence that it does.)
  5. Improves the flavor. That’s a matter of taste. Some people might enjoy the sour flavor; some will want to add a sweetener; some will prefer the taste of other beverages. “The key is to drink water throughout the day (no matter what you add to it) so you can stay hydrated and feel your best.” (The admonition to drink water throughout the day is based on a myth. For most people, it’s sufficient to drink [water or any other beverage] when they feel thirsty or notice decreased urination.)

But …

How much vitamin C is there in “a squeeze of lemon juice”? Not much. A whole medium lemon contains 92 percent of the daily requirement of vitamin C. Vitamin C is essential to prevent scurvy and support vital functions, and it is not stored so it must be ingested regularly. But many other foods are rich in vitamin C, including thyme, parsley, kale, broccoli, and strawberries. Unless you are suffering from vitamin C deficiency, you probably don’t need additional vitamin C. Any excess will just be excreted in the urine. Will your toilet be healthier? I doubt it.

And what about adverse effects? Dentists warn that drinking lemon water can damage tooth enamel

Conclusion: Despite the Name, Dr. Oz Is No Wizard 

If you enjoy drinking warm water with a squeeze of lemon juice, go ahead. But don’t feel obligated to drink it in the belief that it will improve your health. Get your vitamin C from a varied, healthy diet with an emphasis on fruits and vegetables. Drink whatever liquids you enjoy and drink them whenever you are thirsty. The land of reality is preferable to the land of Oz.

This article was originally published as a SkepDoc’s Corner column on the  CSI website

Dr. Hall is a contributing editor to both Skeptic magazine and the Skeptical Inquirer. She is a weekly contributor to the Science-Based Medicine blog and is one of its editors. She has also contributed to Quackwatch and to a number of other respected journals and publications. She is the author of Women Aren’t Supposed to Fly: The Memoirs of a Female Flight Surgeon and co-author of the textbook, Consumer Health: A Guide to Intelligent Decisions.