Sparkling or Still Water for Stomach Upset and Constipation?

“Natural bubbling or sparkling mineral waters have been popular for thousands of years,” but manufactured sparkling water was first “‘invented’ in the mid to late 1700s” when a clergyman suspended water over a vat of fermenting beer. “For centuries, carbonated water has been considered capable of relieving gastrointestinal symptoms, including dyspepsia,” or tummy aches. But we didn’t have good data until a study was published in 2002, which I discuss in my video Club Soda for Stomach Pain and Constipation. Twenty-one people with dyspepsia, which was defined in the study as “pain or discomfort located in the upper abdomen” including bloating, nausea, and constipation were randomized to drink one and a half quarts of either carbonated or tap water every day for two weeks.

Carbonated water improved both dyspepsia and constipation compared to tap water. “Drink more water” is a common recommendation for constipation, but researchers didn’t observe a clear benefit of the added tap water. It seems you need to increase fiber and water rather than just water alone, but sparkling water did appear to help on its own. The study used a sparkling mineral water, though, so we can’t tell whether these effects were due to the bubbles or the minerals.

There’s been a concern that carbonated beverages may increase heartburn and GERD, acid reflux disease, but that was based on studies that compared water to Pepsi cola. Soda may put the pepsi in dyspepsia and contribute to heartburn, but so may tea and coffee in those who suffer from heartburn. That may be partly from the cream and sugar, though, since milk is another common contributor to heartburn. Carbonated water alone, though, shouldn’t be a problem.

Similarly, while flavored sparkling drinks can erode our enamel, it’s not the carbonation, but the added juices and acids. Sparkling water alone appears 100 times less erosive than citrus or soda. So, a sparkling mineral water may successfully help treat a stomach ache and constipation without adverse effects, unless you’re the teenage boy who opened a bottle of sparkling wine with his teeth or the nine-year-old boy who tried to do so on a hot day after he’d shaken it up, actions placing them at risk for a pneumatic rupture of the esophagus.


For more on combating acid reflux, see Diet and GERD Acid Reflux Heartburn and Diet and Hiatal Hernia.

Some of my other videos on beverages include:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

What About Canned Fruit?

Food cans used to be soldered with lead compounds—so much so that people living off of canned food may have died from lead poisoning. Thankfully, this is no longer a problem in the United States. Lead contamination was one of the first priorities of the Food and Drug Administration back in 1906, before it was even called the FDA. Newspapers now have online archives going back a century so we can read about landmark historical events like “FDA Proposes Lead-Soldered Cans Be Banned” from way back yonder in…1993. So even though it was a priority in 1906, the ban didn’t actually go into effect until 1995. Evidently it was complicated because lead solder was “grandfathered” in as a “prior-sanctioned” substance.

Now that the lead is gone, though, are canned foods healthy? It depends primarily on what’s in the can. If it’s SPAM or another processed meat product, for instance, I’d probably pass.

What about canned fruit? We know fruits and vegetables in general may help protect us from dying of cardiovascular disease, and, when it comes to preventing strokes, fruit may be even more protective. But whether food processing affects this association was unknown, as I discuss in my video Is Canned Fruit as Healthy? One study found that unprocessed produce, mostly apples and oranges, appeared superior to processed produce. But that study focused mainly orange and apple juice. It’s no surprise whole fruit is better than fruit juice.

What about whole fruit when it is in a can? Dietary guidelines encourage eating all fruit whether it’s fresh, frozen, or canned, but few studies have examined the health benefits of canned fruit…until now. Canned fruit did not seem to enable people to live longer. In fact, moving from fresh or dried fruit to canned fruit might even shorten one’s life. Therefore, perhaps dietary guidelines should stress fresh, frozen, and dried fruit rather than canned.

Why the difference? While there’s no longer lead in cans these days, there is bisphenol A (BPA), the plastics chemical used in the lining of most cans. BPA can leach into the food and might counterbalance some of the fruits’ benefits. Recently, for example, blood levels of this chemical were associated with thickening of the artery linings going up to the brains of young adults. Canned fruit is often packed in syrup, as well, and all that added sugar and the canning process itself may diminish some nutrients, potentially wiping out 20 to 40 percent of the phenolic phytonutrients and about half of the vitamin C.

Maybe one of the reasons citrus appears particularly protective against stroke is its vitamin C content. It appears the more vitamin C in our diet and in our bloodstream, the lower the risk of stroke. And the way to get vitamin C into the bloodstream is to eat a lot of healthy foods, like citrus and tropical fruits, broccoli, and bell peppers. “Therefore, the observed effect of vitamin C on stroke reduction may simply be a proxy for specific foods (eg, fruits and vegetables) that causally lower stroke” risk. How could the researchers tell? Instead of food, they gave people vitamin C pills to see if they worked—and they didn’t.

This might be because citrus fruit have all sorts of other compounds associated with lower stroke risk, proving that the whole is greater than the sum of its parts. You can’t capture Mother Nature in a pill. It’s like the apocryphal beta-carotene story. Dozens of studies showed that people who ate more beta-carotene-rich foods, like greens and sweet potatoes, and therefore had more beta-carotene circulating in their system, had lower cancer risk. What about beta-carotene supplements instead of whole foods? Researchers tried giving beta-carotene pills to people. Not only did they not work, they may have even caused more cancer. I assumed the National Cancer Institute researcher who did this study would conclude the obvious: produce, not pills. But, no. Instead, the researcher questioned whether he should have tried lower dose pills, alpha-carotene pills, pills with other phytochemicals, or maybe multiple combinations. After all, he said, “[i]t is likely that neither the public nor the scientific community will be satisfied with recommendations concerned solely with foods…”


Check out my other videos on the can-lining chemical BPA, including:

Is fresh fruit really that healthy? See:

Is it possible to get too much of a good thing? See How Much Fruit Is Too Much?.

Now that there’s no more lead in the cans, are there any other ways we’re exposed to the toxic heavy metal? I did a whole series on lead, which you can watch. See also:

I close with yet another screed against reductionism. For more on that, see my videos Why Is Nutrition So Commercialized? and Reductionism and the Deficiency Mentality.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Health Benefits of Citrus Zest

New data demonstrating a DNA protective agent present in at least some fruits and vegetables found that the agent was heat sensitive and determined it was not vitamin C. This was confirmed in a study that tried vitamin C directly and found no effect on DNA protection or repair of DNA strand breaks.

If not vitamin C, what could the DNA protective agent be? The carotenoid beta-cryptoxanthin, found primarily in citrus, seems to be at least one candidate, as I discuss in my video Citrus Peels and Cancer: Zest for Life? If you expose cells to a mutagenic chemical, you can cause physical breaks in the strands of DNA. However, in less than an hour, our DNA repair enzymes can weld most of our DNA back together. What happens if we add some of that citrus phytonutrient? We can effectively double the speed at which DNA is repaired. But, this was determined in a petri dish. What about in a person?

In one study, subjects drank a glass of orange juice and their blood was drawn two hours later. The DNA damage induced with an oxidizing chemical dropped, whereas if they had just had something like orange Kool-Aid instead of orange juice, it didn’t help.

So, do people who eat more fruit walk around with less DNA damage? Yes, particularly women. Does this actually translate into lower cancer rates? It appears so: Citrus alone is associated with a 10 percent reduction in odds of breast cancer.

Given to newly diagnosed breast cancer patients, citrus phytonutrients were found to concentrate in breast tissue, though many complained of “citrus burps” due to the concentrated extract they were given. So, researchers evaluated topical application as an alternative dosing strategy, recruiting women to apply orange-flavored massage oil to their breasts daily. This request was met with excellent compliance, but it didn’t work. We actually have to eat, not wear, our food. 

Why not just take carotenoid supplements to boost our DNA repair? Because it doesn’t work. Although dietary supplements did not provoke any alteration in DNA repair, dietary supplementation with carrots did. This suggests that “the whole food may be important in modulating DNA repair processes…”

Though orange juice consumption was found protective against childhood leukemia, it was not found protective against skin cancer. “However, the most striking feature was the protection purported by citrus peel consumption” . Just drinking orange juice may increase the risk of the most serious type of skin cancer. Daily consumption was associated with a 60 percent increase in risk. So, again, better to stick with the whole fruit. We can eat citrus extra-whole by zesting some of the peel into our dishes.


Now you know why my favorite citrus fruit is kumquat—because you can eat the peel and all!

For other foods that may keep our DNA intact, see my Which Fruits and Vegetables Boost DNA Repair? video. Kiwifruit (Kiwifruit and DNA Repair), broccoli (DNA Protection from Broccoli), and spices (Spicing Up DNA Protection) may also fit the bill.

Interested in learning more about citrus? Check out:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: