Study: It’s best not to test five-second rule

So, I keep hearing different things about the five-second rule. Is it OK to pick up food and eat it after it has dropped to the floor?

Um, no. It’s not OK. At least not if you’re concerned about the potential for foodborne illness.

Your confusion is understandable, though. Just a few years ago, a researcher at Aston University in the United Kingdom announced that the five-second rule was really a thing. The professor led his final-year biology students in a study examining whether bacteria would contaminate different types of foods when they were dropped onto different floor types and left for different times — from three to 30 seconds. They found that time is a significant factor in the transfer of bacteria to a piece of food, and that the type of flooring also has a significant impact. Although the research was never published in a scientific journal, a university press release quoting the professor concluded that, while it carries some risk, the five-second rule “is real.”

Today, we have evidence that’s a little more definitive. A Rutgers University study published online in September in the American Society for Microbiology’s journal, Applied and Environmental Microbiology, concluded that, depending on circumstances, bacteria can transfer onto food dropped onto the floor nearly instantaneously, in less than a second.

The researchers were incredibly methodical in this study. First, they tested four different foods: watermelon, bread, bread and butter, and gummy candy. They tested four different contact times: less than one second, five seconds, 30 seconds, and five minutes. They tested four different surfaces: stainless steel, ceramic glazed tile, maple laminate wood and indoor-outdoor carpet. And they tested two different solutions that they used to spread the bacteria.

For the study, each surface was inoculated with a non-disease-causing “cousin” of Salmonella called Enterobacter aerogenes. The researchers waited until the surface was completely dry, and then dropped food samples onto them for the different time periods. In all, they collected and tested 2,560 samples.

As in the other study, these researchers found that bacteria’s ability to transfer onto food varies depending on circumstances. Foods with higher moisture content — in this case, watermelon — were the quickest and easiest to get contaminated. The researchers said that this isn’t surprising, since bacteria tend to move with moisture.

As for surfaces, tile and stainless steel seemed to be the most susceptible in allowing foods to become contaminated. The indoor-outdoor carpet allowed the least contamination.

Also, the longer the food was in contact with the surface, the more likely it was to become contaminated. Even the solution used to spread the bacteria seemed to make a difference.

Conclusion? Don’t count on the five-second rule to protect you. This study is a reminder to keep all surfaces around meal preparation and consumption clean. And if your food falls to the floor, think twice instead of just popping it into your mouth.

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043, or

Editor: This column was reviewed by Sanja Ilic, food safety specialist for Ohio State University Extension.

For a PDF of this column, please click here.

Kids not eating fruit? Try cutting, slicing it

 How can I get my grandchildren to eat more fruits and vegetables when they’re visiting? I am lucky that I get to have them over often, but I can’t seem to entice them to eat much produce.

You’re not alone. Most children (and teens and adults for that matter) don’t eat enough fruits and vegetables, according to data from the U.S. Department of Agriculture.

But for kids, you might try thinking small. That is, if you don’t already, try slicing fruits and vegetables into bite-size pieces. You might be surprised at the results.

Research by the Food and Brand Lab at Cornell University indicates that slicing fruit could increase consumption, at least in school cafeterias. You might find similar success at home.

For the study, published in 2013 in the American Journal of Preventive Medicine, researchers first interviewed 23 elementary and middle school students and found two primary reasons why they avoided fresh fruit. Surprisingly, younger students said they found whole fruit to be too large and cumbersome to eat comfortably. Students with braces or missing teeth said the same thing. The second reason? The older students, particularly girls, said they felt the whole fruit was messy and unattractive to eat in front of others.

The researchers decided to test how slicing fruit, specifically apples, would affect consumption. They provided eight elementary schools with a commercial apple slicer. When students requested an apple, a cafeteria worker would slice it before giving it to the student. By doing so, the sales of whole fruit increased in the schools by an average of 61 percent.

The researchers then followed up their study in middle schools. Of six middle schools in a district, three were provided the commercial apple slicer, and three weren’t. In all, the slicers increased average daily apple sales by 71 percent. The researchers also examined cafeteria waste to determine how much of the apples served were eaten. They found that in schools with the fruit slicers, the percentage of students who ate more than half their apple increased by 73 percent.

This all points to how important it can be to pay as much attention to how food is served as to which food is served when it comes to encouraging kids to eat fruits and vegetables. Other research has shown that promoting cafeteria salad bars with superhero-type characters can increase consumption of vegetables. And, of course, children tend to pick up habits from watching important adults in their lives, so be sure to model the behavior you want to see them imitate.

Another thing to consider, depending on how old your grandchildren are, is to make sure there are no choking hazards. The USDA suggests cutting foods like grapes and cherry tomatoes in half before serving them to preschoolers.

For more information about overcoming barriers to eating healthy, take a look at the Cornell lab’s website at For tips from the USDA according to age group, see

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043, or

Editor: This column was reviewed by Carol Smathers, field specialist for Ohio State University Extension in Youth Nutrition and Wellness.

For a PDF of this column, please click here.

Restrictive diet can help ease intestinal issues

 I have a friend who no longer eats wheat products, onions, garlic or a lot of other foods. She said it’s because she has been experiencing stomach problems and a “low-FODMAP” diet was recommended. It sounds serious. What is it?

FODMAP is an acronym used for foods containing certain carbohydrates that aren’t absorbed well in the intestines and can be rapidly fermented in the gut. In some people, they cause gas, bloating, abdominal pain, excess fluid, constipation and diarrhea. The acronym stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols — a mouthful, which is why you will hear the term “FODMAPs” a lot more often than the actual words it stands for.

The low-FODMAP diet was developed in the last 10 years by Australian researchers to treat people with irritable bowel syndrome. The syndrome is pretty common, but relatively few people have severe symptoms. It is sometimes confused with the more serious inflammatory bowel disease, which includes Crohn’s disease. The conditions have similar symptoms, but people with inflammatory bowel disease can also experience rectal bleeding and fever, and the disease can cause serious complications, including intestinal blockages, ulcers in the intestine and problems getting enough nutrients. Although it’s a separate medical condition, there is some evidence that a low-FODMAP diet could help people with this disease, as well. But the bulk of studies have focused just on people with irritable bowel syndrome.

One recent study, published earlier this year in the journal Gastroenterology, followed more than 90 patients for six weeks. Half followed the low-FODMAP diet, while the other half — the control group — simply avoided large meals, binges, and caffeine and alcohol, which are known to irritate the gut. More than 50 percent of the low-FODMAP group reported major improvement in abdominal pain, while only about 20 percent of those in the control group did.

Unfortunately, it can be difficult for consumers to identify low-FODMAP foods, and, as the diet regimen is relatively new, the list of foods continues to be updated. Among the foods to be avoided are asparagus, artichokes, onions, garlic, snow peas, cabbage, cauliflower, celery, mushrooms, sweet corn, apples, cherries, pears, mango, nectarines, peaches, plums, watermelon, apricots, dates, milk, yogurt, cream cheese or other soft cheese, ice cream, rye, wheat breads, wheat pasta, cashews, pistachios, honey, agave, high-fructose corn syrup, and other sweeteners including sorbitol, mannitol and xylitol. According to the Academy of Nutrition and Dietetics, while soy milk and silken tofu are high in FODMAPs, firm tofu is low, and soybean oil is FODMAP-free.

It can be easy for people who self-restrict on the low-FODMAP diet to fall into a diet too low in fiber or dairy and miss out on important nutrients. So, it’s strongly recommended that anyone following a low-FODMAP diet do so under the care of a gastroenterologist or registered dietitian familiar with the diet. After initial restrictions, the medical team can reintroduce higher-FODMAP foods and monitor for symptoms that may recur.

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043, or

Editor: This column was reviewed by Carolyn Gunther, specialist for Ohio State University Extension in Community Nutrition Education.

For a PDF of this column, please click here.

What will happen when fiber is no longer fiber

 I understand that the recommendation for fiber intake is going up. When will we see that reflected on Nutrition Facts labels?

The new labels should be on foods by July 2018. And you’re right, the Daily Value — the number on Nutrition Facts labels that indicates the recommended intake for nutrients — is increasing from 25 grams of fiber a day to 28. As with any Daily Value number, this is the recommended level for someone eating a 2,000-calorie-a-day diet. The higher number is based on findings of the Institute of Medicine, which recommends that people consume 14 grams of fiber for every 1,000 calories consumed. Unfortunately, most people don’t get nearly that amount.

Along with Daily Value update, the Food and Drug Administration also actually provided a definition of what counts as fiber for Nutrition Facts labels. And unless the rules are updated before taking effect, some fiber that’s included in many processed foods today won’t meet the new standard.

There are many different types of fiber, and they don’t all act in the body the same way. So, in the new definition, the FDA requires that any fiber included on the Nutrition Facts listing have an established “beneficial physiological effect” — that is, it has to be considered beneficial to human health. Such benefits include reduced blood glucose, cholesterol or blood pressure; increased satiety, which would help people reduce calorie intake; improved laxation or bowel function; and increased absorption of minerals, such as calcium.

The FDA will allow any fiber that’s intrinsic and intact in the food itself — the fiber naturally found in fruits, vegetables and whole grains, for example — to be included in the grams listed under “fiber” on the new labels. But it won’t include everything.

Today, food manufacturers often extract and isolate fiber from foods to add to high-fiber breakfast bars, protein shakes, cereals, breads, yogurts, granolas and even calorie-free sweeteners. They can also chemically synthesize some types of fiber.

These “isolated or synthetic” types of fiber not only provide additional fiber to the processed food, but also often help provide the flavor and texture that the food manufacturer is looking for in the finished product. However, not all types of this kind of fiber have been shown to have the human health benefits the FDA is looking for.

So far, the FDA lists 25 fibers in this category as making the grade, allowing them to be counted as fiber. They include psyllium husk, guar gum, pectin and cellulose. But in its review of the scientific literature, the FDA could not find health benefits of other types of fiber often used in processed foods, including inulin, bamboo fiber, soy fiber, pea fiber and wheat fiber. As it stands now, those ingredients, like all fiber, would have to be included in the amount of carbohydrate in the food but would not be counted in the amount of fiber.

The agency could update the list of what’s allowed to be included in the fiber listing as scientific evidence develops. But as it stands today, many of the “high-fiber” foods you see on grocery store shelves may no longer meet that criteria under the new rules.

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043,

Editor: This column was reviewed by Dan Remley, field specialist for Ohio State University Extension in Food, Nutrition and Wellness.

For a PDF of this column, please click here.


The scoop on fresh, homegrown tomatoes

 We are enjoying fresh vegetables from our garden, especially the tomatoes. But we have a disagreement about whether or not they are actually healthier than store-bought fresh or even canned tomatoes. We each think we’ve read information that contradicts the other. Who’s right?

You’re both right, depending on a few factors.

There are few things better than biting into a fully ripe, meaty, juicy tomato fresh-picked from the garden. And as long as it doesn’t sit around on the kitchen counter very long, you will get the peak amount of nutrition that the tomato has to offer.

Homegrown vegetables have two things going in their favor over store-bought: They have a longer time on the vine, and they have a shorter time in storage and, of course, transport. Tomatoes sold at the grocery store are usually picked before they’re completely ripe so they can withstand the rigors of being boxed up and transported across the state, the country or even the ocean. Before they’re sold, they’re ripened artificially with ethylene, a gas that plants actually produce naturally. But that results in a ripeness that’s not quite the same as when you pick that love apple off the vine yourself at peak maturity. That’s when fruits and vegetables typically have the most vitamins, minerals and other nutrients.

To retain the most nutrients, store your fresh produce properly. While 55 degrees F is the optimal storage temperature for tomatoes, room temperature will do, and keep them out of direct sunlight. Proper storage helps slow the respiration process. After being picked, produce continues to “breathe,” or respire, breaking down carbohydrates to use as energy and resulting in the loss of flavor and nutrients. Some types of produce, such as asparagus, broccoli, mushrooms, peas and sweet corn, have higher respiration rates than others and are more perishable. Others, such as apples, garlic, grapes, onions and potatoes, have low respiration rates, allowing them to be stored for a longer time and still retain their quality. Tomatoes are in between, classified with carrots, peaches, pears, lettuce and peppers as having a moderate respiration rate.

When produce is commercially canned or frozen, it is processed immediately after harvest to take advantage of the product’s peak ripeness and to lock in as many nutrients as possible. The product is then stored in a way to protect it from heat, light and oxygen, all of which naturally destroy nutrients. So, compared with “fresh” produce that may have been picked before it was fully ripe and spent days or weeks in less-than-optimal storage or transport conditions, canned and frozen versions often retain more of the original nutrients.

Canned tomatoes also provide another benefit: A phytonutrient in tomatoes, lycopene, is absorbed more readily by the body from processed tomatoes than fresh. Lycopene has been associated with a lower risk of prostate cancer. So, in that way, canned tomatoes are more beneficial than fresh.

For more about nutrients in tomatoes and other produce, see

Editor: This column was reviewed by Irene Hatsu, food security specialist for Ohio State University Extension.

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043,

For a PDF of this column, please click here.