TIME Diet/Nutrition

Here’s What Happens To Your Steak When You Grill It

Nothing says the Fourth of July like juicy seared food, so here’s a quick lesson on the science behind grilling

It’s time to throw nearly everything you can think of—meat, chicken, fish, vegetables and even fruit—on the grill and give it a good sear. But what makes food cooked over a fire taste so good? Here’s the simple (we promise, it’s not that complicated) science behind what makes red meat red, when to take your food off the flame, and whether gas or charcoal is really better for that getting that smoky flavor, thanks to the experts at the American Chemical Society.

TIME Diet/Nutrition

5 Foods That Taste Better in July Than They Will All Year

Here's what should be on your grocery list this month

Never know what’s growing now? Let’s take it one month at a time, with TIME‘s Foods That Taste Better Now Than They Will All Year.

We’re officially into summer, which means the produce department is looking plentiful. “It depends on where you are and what your climate is, but July is a great month,” says Deborah Madison, author of Vegetable Literacy. While some farmer’s markets will have different offerings compared to others, keep your eyes out for some of these fruits and veggies.

Figs: “There’s the early crop of figs this year, and there will be a second crop at the end of August,” says Madison, who lives in New Mexico. Just rinse your figs and trim the stems before eating.

Cherries: Madison says farmer’s market shoppers will likely continue seeing cherries brought to market, though the types of cherries may change as the season goes on. We are smack in the middle of both the tart and sweet cherry season now, so there’s no better time to pick up a pint.

Peas: Keep an eye out for the bright green pea pods. Peas taste their best in the summer, and according to Vegetable Literacy, if you live in higher altitudes, peas can be enjoyed all summer long. Snap peas taste their best when they are moist. When they start to dry, they can taste more starchy.

Peaches: If you can smell peaches, they’re ripe. While peach season can peak in states at different times, you’re definitely going to see some especially juicy ones in July. Peaches should be firm and without bruises on the outside.

Rhubarb: This vegetable is hearty since it comes from places with tough climates like China, Mongolia and Russia. Rhubarb can begin to appear in the Spring, but it can have a long summer season in some states. Remember to only eat the stalks and not the leaves, which are poisonous. Most of us enjoy rhubarb in our pie, but it can be good as a jam or can be eaten like applesauce.

TIME Diet/Nutrition

This Kind of Food Is Why America Is So Fat, Study Says

TIME.com stock photos Food Snacks Candy Chocolate
Elizabeth Renstrom for TIME

More calories in our food supply means more overeating

Worldwide, countries are dealing with a serious obesity problem. In the U.S. alone, more than two thirds of adults are overweight or obese. Now a new study suggests it likely has a lot to do with the make up of our food.

The new study, published in the Bulletin of the World Health Organization, looked at both the obesity rates and the supply of energy-dense—meaning high-calorie—foods in 69 countries, and found that both body weight and calories had increased in 56 of those states since 1971.

The finding was especially notable in high-income countries. “This suggests that, in high-income countries, a growing and excessive food supply is contributing to higher energy intake, as well as to increasing food waste,” the authors write. In the U.S. alone, the food energy supply went up by 768 calories per person between 1971 and 2008.

A wide reduction in physical activity may also be a contributing factor, the authors note, however, the surplus of available calories is likely leading people to overeat which in turn is adding on pounds for a lot of people. Other factors like pollution and gut bacteria should also be further studied to understand how they may contribute to weight gain as well, the researchers argue.

To combat the problem, the researchers argue that comprehensive approaches will be necessary. For instance, nation-wide policies should restrict the marketing of unhealthy food to young people and more packaged foods should have front of box nutritional labeling.

As always, eating more fresh foods rather than processed and exercising are two healthy habits worth adopting.
TIME Research

Your Diet May Be Causing Your Urinary Tract Infections

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A new study reveals that factors related to diet might play a part in urinary tract infections

Tough-to-treat urinary tract infections (UTI) that are resistant to antibiotics are on the rise. Now, in a new study looking at human urine published in the Journal of Biological Chemistry, researchers say they’ve discovered why some people are more prone than others to the infections. Intriguingly, diet may have something to do with it.

Early on in an infection, cells produce a protein called siderocalin that blocks bacterial growth, including the growth of E. coli that often causes UTIs, says Jeffrey P. Henderson, MD, PhD, assistant professor of medicine at Washington University School of Medicine in St. Louis and senior author of the study. (It does this by keeping iron away from the bacteria, which need it to thrive.) The researchers wanted to see how the protein worked differently in various samples of urine at restricting the growth of E. coli, so they analyzed the urine from about 50 men and women.

“We found, kind of to our surprise, that there was a really wide range between individuals and how well this protein worked, just depending on that individual’s urinary composition,” says Henderson.

Two common factors emerged in urine that had a better ability to resist bacterial growth: it had a high pH—one that’s more alkaline, in other words—and higher levels of certain metabolites formed by gut microbes. That metabolite isn’t made from human cells, Henderson says; rather, they come from the diet or are metabolized by bacterial cells from dietary sources. “It looks like this protein that’s part of your immune system is able to use metabolites in the diet as grips to hold onto iron and keep it away from pathogenic bacteria,” Henderson says. In some people, that system is set up really well, he says, but in those who get recurrent UTIs, it doesn’t seem to work as well.

Both urine pH and metabolite production may be able to be changed through diet, and doing so could potentially offer a treatment strategy in the future, he says. “It may be that we have to adjust multiple things at the same time to get the system to work well, but the appealing part is this is not an antibiotic strategy,” he says. It may allow you to keep your normal flora while keeping bacteria out of the urinary tract.”

Physicians already know how to raise urinary pH with things like calcium supplements, and alkalizing agents are already used in the U.K. as over-the-counter UTI treatments, Henderson says. Knowing how to encourage the metabolites is trickier. The molecules come from phenolic, or aromatic, compounds, Henderson says, and robust food sources include those that we more often hear are rich in antioxidants: coffee, tea, colorful berries, red wine and dark chocolate.

And yes: cranberries, too, are known to make urinary aromatics, which may be why cranberry products are so often used as UTI remedies, Henderson says. “One thing this suggests is that maybe the reason it’s not more effective is that people need both cranberries and a higher urine pH, or they need cranberries and appropriate inhabitants of their intestine, or the right microbiome composition in their gut, for the cranberry part to work properly.”

A treatment without antibiotics would be a boon, but it’s likely a several-pronged approach and for now, more research is needed. “We still have a few more details to iron out before we know exactly how to do that.”

TIME Diet/Nutrition

New York City Restaurants Are Cleaner Than Ever

18% fewer eateries have been cited for evidence of mice

It’s been five years since New York City instituted a strict grading policy assessing restaurants for cleanliness, food safety and handling—an attempt to address its somewhat unsavory reputation as a mecca for unsanitary eating establishments.

Now, in the latest report, city health officials have some good news: 95% of restaurants now earn A grades, and violations that can contribute to foodborne illnesses have dropped by 11%, giving New York its cleanest report card since the program began.

The requirements and methods of the health inspections are not without critics; even high-end establishments with Michelin-star honored chefs like Per Se were notoriously cited for not maintaining hot foods at high enough temperatures or cold foods at cold enough temperatures, despite commonly used practices of “resting” dishes after they come out of the oven or refrigerator to balance flavor and temperature. But the system works, say health officials. The report says that 37% more new restaurants in the city earn A grades in their first year compared to five years ago, and 18% fewer eateries have been cited for evidence of mice.

The program allows eating establishments one do-over; if they don’t meet criteria for earning an A grade, they have up to 30 days to fix their violations and receive a second inspection before getting the final grade that gets posted on their window. That posting, says Dan Kass, deputy commissioner for environmental health at the New York City Department of Health and Mental Hygiene, is key to the program’s success. “You need transparency in governmental inspection programs,” he says. “It’s the best way to inform the public and encourage them to vote with their feet and the best way to motivate restaurants—especially those that lag behind others in hygiene and food safety practices—to feel motivated to comply [with health regulations.]”

When the letter grading and public posting of the grades began five years ago, says Kass, officials expected about a 5% improvement in grades every year. “We have seen much more rapid change than that,” he says, “and it truly influences the practice of food safety in restaurants.”

The department now plans to launch a food safety workshop for restaurant workers—not just owners—to help them better understand the value and importance of proper handling and storing of food. But the public and prominent posting of letter grades will remain, so diners will still have a quick and easy way of knowing where the restaurant stands with respect to food safety and sanitation. “Inspections and education alone are insufficient to drive restaurants to improve,” Kass says. “Threats of fines may help, but those too are insufficient to move some restaurants to really change practices and put the public’s health first. There is no question that public transparency and making the information available to public at the point of sale is probably the most important driver—at least for the improvements we see.”

In fact, the system is gaining in popularity; Yelp reviews now include the grades or number scores for restaurants in cities that provide them.

TIME Diet/Nutrition

The Strange Link Between Junk Food and Depression

TIME.com stock photos Food Snacks Candy Chocolate
Elizabeth Renstrom for TIME

Some—but not all—sugars were associated with depressive disorders

Of our many modern diseases, one of the biggest burdens on society is an unexpected one: depression, according to the World Health Organization. And what we eat may be contributing, finds a new study published in the American Journal of Clinical Nutrition.

James E. Gangwisch, PhD, assistant professor at Columbia University in the department of psychiatry, wanted to find out whether foods with a higher glycemic index (GI)—a scale that ranks carbohydrate-containing foods by how much they raise your blood sugar—would be associated with greater odds of depression. “When I was a kid, I was almost like a candy junkie,” Gangwisch says. “I noticed for myself, if I eat a lot of sugar, it makes me feel down the next day.” Gangwisch says he stopped eating added sugar years ago but remained curious about whether a junk food diet could make people depressed.

He and a team of researchers looked at data from food questionnaires and a scale that measures symptoms of depressive disorders from postmenopausal women in the Women’s Health Initiative Observational Study. The data came from roughly 70,000 women, none of whom suffered from depression at the study’s start, who had baseline measurements taken between 1994 and 1998, and then again after a three-year follow-up.

Diets higher on the glycemic index, including those rich in refined grains and added sugar, were associated with greater odds of depression, the researchers found. But some aspects of diet had protective effects against developing depression, including fiber, whole grains, whole fruits, vegetables and lactose, a sugar that comes from dairy products and milk that sits low on the glycemic index.

Added sugars—but not total sugars or total carbohydrates—were strongly associated with depression.

Though the authors couldn’t pinpoint a mechanism from this study—it was associative—they note that one possibility is that the overconsumption of sugars and refined starches is a risk factor for inflammation and cardiovascular disease, both of which have been linked to the development of depression.This kind of diet could also lead insulin resistance, which has been linked to cognitive deficits similar to those found in people with major depression.

Further research is needed, Gangwisch says, and it’s not yet known whether the results would translate to a broader group of people, including men and younger women. But even now, diet may be worth discussing with people who suffer from depression, Gangwisch says—even though doing so may be difficult. “It’s hard enough to get the general public to avoid those kinds of foods, but it’s even harder to get someone who suffers from depression to avoid them and give them up,” he says. “You don’t want people to feel guilty either…to say, ‘Your diet’s bad and you should change it,’ would take kind of a soft sell approach.” Still, he believes the effort is worth it. “I think it’s important and I think it has a big effect on your mood and how you feel and your energy level,” he says. “If it’s something that people can change, they really would benefit from it.”

TIME Diet/Nutrition

5 Delicious Banana-Free Smoothie Recipes

From strawberry basil to fudgesicle

Bananas are ubiquitous in smoothie recipes, but don’t go bananas if you’re allergic to the tropical fruits, don’t like them, or just don’t have any on hand: You don’t have to miss out on good-for-you shakes. Just blend up one of these banana-free treats and sip away.

A few notes:

For all of these recipes, combine the ingredients in a blender—preferably high-speed, like the Vitamix ($382, amazon.com)—and blend until smooth. If the smoothie is too thick, add water a bit at a time until it’s the consistency you like.

We gave suggested serving sizes, but remember that smoothie calories add up. Have a larger serving if the smoothie is a meal. If it’s a snack, pour it into a smaller cup and sip slowly.

Don’t leave out the pinch of salt. Your smoothie won’t be salty, but it will have a brighter flavor.

If you’re going to use almond milk, beware of packaged brands with fillers and sweeteners. One way to avoid all that is to make your own; it’s super-easy to DIY.

  • Strawberry Basil Smoothie

    strawberry-basil
    Beth Lipton

    Serves: 1

    1 cup milk (dairy, almond, rice, coconut) or plain yogurt

    1 cup frozen strawberries

    1/2 cup frozen spinach

    ¼ cup fresh basil leaves

    2 Tbsp. hemp seeds or almond butter

    1 Tbsp. honey

    ½ tsp. vanilla extract

    Pinch of salt

     

  • Peachy-Green Smoothie

    peachy-green
    Beth Lipton

    Serves: 1

    1 cup milk (dairy, almond, rice, coconut) or plain yogurt

    1 1/2 cups frozen peach slices

    1/2 cup frozen spinach

    2 Tbsp. flax-chia or flax-hemp blend (such as Carrington Farms, $6.50 for 12 oz., amazon.com)

    1 tsp. greens powder, optional (I like Sunfood Sun Is Shining, $40 for 8 oz., amazon.com)

    1 Tbsp. pure maple syrup or honey

    ¼ tsp. ground ginger, optional

    Pinch of salt

     

  • Mighty Mango-Coconut Smoothie

    mango-coconut
    Beth Lipton

    Serves: 1

    1 1/4 cups frozen mango chunks

    1/2 cup frozen spinach

    1 cup full-fat coconut milk

    2 Tbsp. hemp or chia seeds, or flax-chia or flax-hemp blend

    1 Tbsp. maple syrup or honey

    Pinch of salt

  • Fudgesicle Smoothie

    fudgesicle
    Beth Lipton

    Serves: 2

    1 cup milk (preferably coconut, but dairy or almond will work. Rice is too thin)

    1/3 cup raw cacao powder (such as JoyFuel, $18 for 1 lb., amazon.com)

    ½ cup frozen spinach

    ½ avocado, peeled and pitted

    3 Tbsp. maple syrup or honey

    pinch of salt

    1 cup ice cubes

  • AB&J Smoothie

    abj
    Beth Lipton

    Serves: 2

    1 cup milk (dairy, almond, rice, coconut) or plain yogurt

    1/2 cup frozen spinach

    1 cup frozen mixed berries

    ¼ cup almond butter

    ¼ cup oats

    1 Tbsp. honey or maple syrup

    Pinch of salt

    This article originally appeared on Health.com

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TIME Diet/Nutrition

In Defense of Fiber: How Changing Your Diet Changes Your Gut Bacteria

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Danny Kim for TIME

Finally, the motivation you've been waiting for to gorge yourself on fiber

You no longer live in a world where you can pretend you’re only eating for one; the trillions of bacteria in your gut, we now know, also feed on what you put in your mouth—and they behave very differently depending on what that is.

It’s increasingly clear that the composition of your gut bacteria likely influences your risk for many health problems, from obesity and type-2 diabetes and even certain autoimmune diseases. Scientists are hard at work trying to determine how and why that’s that case, as well as which bacteria are beneficial—and how to protect them. A recent study published in The BMJ adds to the growing evidence that fiber might be a critical gut-nourishing nutrient. (Unfortunately, less than 3% of Americans eat the government-recommended amount daily.)

“You really hold the reins to guiding this community [of bacteria] through the choices you make,” says Justin L. Sonnenburg, PhD, associate professor in the department of microbiology and immunology at Stanford University School of Medicine and author of The Good Gut. Sonnenburg was not involved with this study, but research from his lab also suggests that fiber plays a big role in promoting good bacteria.

The authors of the new study wanted to look at what changes in diet do to one particular gut microbe species: Akkermansia muciniphila—a strain that’s been associated with leanness and better glucose tolerance in mice. They wrangled a group of 49 overweight and obese adults, took stool and blood samples and asked them to follow a six-week calorie-restricted diet (between 1,500-1,800 calories per day) while increasing their fiber intake. The diet was followed by six weeks of eating normally. They kept a food journal throughout, and the researchers biopsied their fat tissue.

The people who had more Akkermansia in their gut from the very start had better clinical measures after they completed the diet, compared to the people with less of the bacterium. Both groups of people lost the same amount of weight, but the high-Akkermansia group had a stronger decrease in visceral fat than the others, says study author Patrice D. Cani, PhD, professor and group leader of the Metabolism and Nutrition Research Group at Université Catholique de Louvain in Belgium. “We discovered that the patients who exhibited higher amounts of Akkermansia were the patients who had a very strong improvement in cholesterol, in glycemia, in waist to hip ratio and also a reduction in different parameters in both cardiovascular disease and risk factors.”

Higher levels of Akkermansia, the findings suggest, seem to have favorable effects on health.

The good news is that your initial Akkermansia levels are not your fate. People who started out with lower stores of Akkermansia had more after they followed the fiber-rich calorie-restricted diet. You can increase these bacterial populations by eating fiber, Cani’s research suggests, which acts as a prebiotic in the gut and has a beneficial effect on some bacteria.

Now, Cani says he is working on an experiment with obese and diabetic patients to administer Akkermansia alone, without any dietary modifications, to see what effect it has on insulin resistance and cardiovascular disease risk factors. “If we can improve these different parameters, that would be something great,” he says.

Here’s why fiber is so important to intestinal flora: gut your microbes feed on it and produce short-chain fatty acids, which get absorbed into the bloodstream and regulate the immune system and attenuate inflammation, Sonnenburg says. “That means if you’re not eating dietary fiber, your immune system may be existing in kind of a simmering pro-inflammatory state,” he says—the very state that predisposes us to different Western diseases. “Our diet and deteriorated microbiota are really a major piece of the puzzle in trying to understand why Western diseases are rising like crazy.”

Sonnenburg says that when researchers try on mice what many of us do on a regular basis—eat food depleted of dietary fiber—their gut microbes behave erratically. “They turn and start eating the mucus lining of the intestine,” says Sonnenburg, “because that’s also a carbohydrate source and it’s kind of a fallback food for them.” In mice on a low-fiber diet, the mucus lining thins to about half of its normal width, he says. It’s so far unclear whether the same thing happens in humans, but Sonnenburg thinks it might. “We start to see these correlates that we think over the course of decades in a human could lead to something problematic,” he says.

Loading up on fiber-fortified processed foods isn’t likely a good way to increase the kind of fiber that benefits the gut. Studies done on single fibers—those, like inulin, which are added to foods—haven’t shown to have the same effects as fiber that occur naturally in whole foods. “All of the vegetables we’re encouraged to eat by our mothers and by the government guidelines, these are all filled with fiber, and filled with a diversity of fiber, and probably the best route for encouraging a diverse microbiota,” Sonnenburg says.

Nuts, seeds, whole grains, legumes and even dark chocolate are high in fiber—as are vegetables. “You can eat massive amounts of plant material and it can be incredibly good for you, you can feel really satisfied and full,” Sonnenburg says. “I find that a really nice way to eat—just kind of gorging myself on plant material.”

TIME Diet/Nutrition

Only a Third of People Consider Their Diet Healthy, Study Says

Fresh Vegetables
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Still, the number is up from last year

In a recent U.K. study, only 34% of people said they consider themselves to have a healthy diet.

Although most people in the study didn’t view their diets as healthy, that figure is still 5% more than last year, according to the 2015 Grocery Eye survey, which was released this month by the market research company Future Thinking. The findings are based on data from more than 2,000 consumers.

Even though there’s been more attention paid to the high sugar content in foods and drinks, 56% of people who answered the survey said they haven’t changed their eating habits because of that information. The research also revealed that when consumers want to purchase healthy food, a third of them will look at the fat content. 22% look at the amount of sugar and 20% use calories as a reference.

Cost may also be a factor when it comes to adopting healthy eating habits, the research suggests. The survey shows that 65% of the consumers believed that eating healthy was more expensive than eating unhealthy and that 52% reported they would eat healthier if it was more affordable.

“There continues to be confusion as to what being healthy really means and what foods you should and shouldn’t eat,” Claudia Strauss, Managing Director of FMCG and Shopper at Future Thinking said in a statement. “Consumers are bombarded with extensive and often contradictory messages which are leaving them feeling unengaged and helpless. It is clear that sugar is the villain of the piece and will likely remain so for a while but quite how to respond to this news is not yet clear for consumers.”

TIME Diet/Nutrition

14 Most Dangerous Summer Foods

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Avoid leaving food out for more than four hours

Who doesn’t love picnics and barbecues? Thing is, if you don’t practice safe food preparation, outdoor eating can also set the stage for foodborne illness. Every year approximately 1 in 6 Americans gets sick, and 128,000 are hospitalized from foodborne diseases, according to the CDC. Among 31 known pathogens, most deaths occur from Salmonella, Toxoplasma, Listeria, and norovirus. “The rule of thumb is that no food should be left out for four total hours,” says Amy Goodson, RD, a dietitian at Ben Hogan Sports Medicine in Fort Worth, Texas. “This refers to not just four hours at a time, but four accumulated hours.” The following foods are most likely to ruin your good time.

Burgers

Undercooked meat puts you at risk for potentially life-threatening illness from a subtype of E. coli bacteria called O157:H7. An outbreak in 2014 linked to ground beef contaminated with this type of E. coli sickened 12 people from four different states. “Your risk largely depends on the number of cows making up your ground beef,” says Michael Schmidt, PhD, professor at the department of microbiology and immunology at the Medical University of South Carolina (MUSC). “The greater the number of cows the greater chance of having something that was not intended to be in the meat.” Ground beef is riskier than specific cuts of meat that come from a single cow. Regardless, cook burgers or any beef to an internal temperature of at least 160 degrees to kill E. coli.

Sprouts

Topping your burger with a handful of raw sprouts could set the stage for food poisoning. Seeds and beans need warm and humid conditions to grow, which also happen to be ideal conditions for the growth of bacteria, including Salmonella, Listeria, and E. coli. Even homegrown sprouts grown under sanitary conditions can produce harmful bacteria because seeds have been known to be contaminated. “If you are putting sprouts in a salad or on a sandwich/burger, consider sautéing them first,” says Goodson. “Sprouts can easily harbor bacteria and when that is mixed with moisture, food poisoning risk multiplies.”

Caesar dressing

Eating a Caesar salad can make you sick if the dressing is made the traditional way—with raw eggs. (Store-bought bottled dressing is pasteurized; it’s homemade dressing you need to watch out for.) “Pay close attention to anything that could be made with raw or undercooked eggs, especially if they are not pasteurized,” says Lori Zanini, RD, a Los Angeles-based dietitian. The Food and Drug Administration recommends cooking eggs thoroughly and washing all equipment that comes in contact with eggs and your hands with hot soapy water.

Leafy green salads

Once you know the dressing’s safe, you also want to consider the lettuce itself—and the hygiene habits of the person who prepared it. A CDC report revealed that salad greens—such as lettuce, escarole, endive, spinach, cabbage, kale, arugula, and chard—caused 262 outbreaks involving 8,836 reported cases of foodborne illness between 1998 and 2008. There are a few ways greens can be contaminated: at the farm by manure or dirty water rinses; when a sick person preps a salad without washing their hands; and by cross-contamination at home (for example, by using the same cutting board for raw meat and salad prep, which spreads bacteria from meat to produce.) Wash greens before eating by placing them in a large colander and tossing them under your faucet, or by using a salad spinner.

Oysters

If a summertime trip to the shore always includes a stop at a raw oyster bar, consume with caution: Vibrio parahaemolyticus and Vibrio vulnificus can both can be contracted by eating raw shellfish, especially oysters. In fact, the CDC reported a 52% increase in Vibrio poisonings between 2011 and 2013. Both of these bacteria cause diarrhea, vomiting, and abdominal pain in healthy people. For people with liver disease, diabetes, cancer, stomach disorders, or any other condition that affects the immune system, Vibrio vulnificus is extremely dangerous: it can invade the bloodstream, causing a life-threatening illness. Half of all Vibrio vulnificus bloodstream infections are fatal.

Homemade ice cream

It sounds like a luscious treat, but homemade ice cream prepared with raw eggs could contain Salmonella, says Leigh Tracy, RD, dietitian at the Center for Endocrinology at Mercy Medical Center in Baltimore, MD. “The FDA recommends using a custard base or pasteurized eggs.” Cooking and pasteurization kills Salmonella. Store-bought ice cream can contain harmful bacteria as well, but it’s much more rare. In 2015, both Blue Bell Creameries of Texas and Jeni’s Ice Cream of Ohio produced ice cream contaminated with Listeria. The Blue Bell ice cream was linked to 10 illnesses, including three deaths. All that said, you generally shouldn’t worry about the safety of store-bought ice cream;Listeria is rarely found in the sweet stuff because it can’t grow at cold temperatures.

Melons

Cantaloupes have been linked to Listeria outbreaks, and watermelon can also cause problems. Listeria traced back to a North Carolina farm and another outbreak in Colorado sickened more than 140 people and resulted in 30 deaths. Unlike other germs, Listeria can grow in refrigerator-level temperatures. It has no smell or taste and only heat can kill it. But if heated food cools, the Listeria may grow again, according to the FDA. Since the germs live on the outside peel, rinse all melons under running water and scrub with a produce brush before eating or cutting the fruit, even if you peel it first. Cutting into the rind can spread bacteria from the outside of the fruit to the inside.

Chicken

Chicken is commonly contaminated with Salmonella and needs to be thoroughly cooked to kill the germs. A 2014 Consumer Reports analysis found that 97% of all chicken breasts, including organic, were contaminated with harmful bacteria. Use a food thermometer when cooking meats and chicken to ensure you’ve heated them to a safe temperature. Chicken should be cooked to an internal temperature of 165 degrees and held at between 140 and 145 degrees, says Goodson. “Plus, be careful of storage practices before it’s grilled,” she says. “For example, don’t put raw chicken or beef, even if wrapped in foil, above the salad or fruit bowl when you are transporting it to the BBQ or party, as fluids can drip and cross-contaminate other foods without you knowing.”

Tomatoes

Tomatoes are super healthy, and can be tossed into salads or sliced as a burger topping. But because they aren’t cooked (which generally kills bacteria) they have been linked to foodborne illness outbreaks. Cases of Salmonella poisoning in 2006 were traced to a packinghouse in Ohio. Overall, 190 people were sickened across 21 states before the source of the outbreak was discovered. Salmonella is found in the feces of animals or in some habitats including ponds as drainage ditches. “It is important to wash your tomatoes thoroughly under running water,” says Tracy. “Additionally, discard any bruised or spoiled tomatoes.”

Deviled Eggs

The risk of Salmonella is highest in deviled eggs when they’re not held at the right temperature (at or below 40 degrees Fahrenheit), says Goodson. Salmonella can live on both the inside and outside of eggs and the egg can still appear perfectly normal, according to the CDC. Deviled eggs are cooked, of course, which should kill any germs in the eggs. But because you combine a bunch of eggs together for the filling, and then it sits for hours at room temperature, bacteria can grow to dangerous levels if an egg is undercooked or contaminated after cooking. Buy eggs only from stores or other suppliers that keep them refrigerated at or below 40 degrees Fahrenheit, and serve deviled eggs on ice at all times.

Macaroni salad

Staphylococcal aureus is type of bacteria found primarily on skin and hair, and can cause food poisoning when a person prepping a dish contaminates it and then fails to refrigerate it properly. It’s most common in foods that require handling, but no cooking—like macaroni salad. Some strains of Staphylococcal aureus are capable of producing a highly heat-stable protein toxin, and unlike some germs that can take up to two weeks to cause symptoms, S. aureus can make you sick within 6 hours and sometimes as little as 30 minutes. Any food that should be held either hot to cold, left in the danger zone (40 to 140 degrees F), puts you at risk for foodborne illness.

Leftovers

Leftovers should be handled properly as well. Once everyone has eaten, put the food in its appropriate hot or cold environment, says Goodson. “Food left out becomes a problem because it enters the temperature danger zone, between 40 and 140 degrees Fahrenheit.” Count how many hours the food has been left out overall. If it’s close to or over four hours, trash it, says Goodson. “Do this especially if the food was left out a good part of the day, and at the hottest part of the day, just get rid of it,” Goodson says. “Don’t take the risk of getting sick.”

Charred meats

Though most summer food hazards come from food poisoning germs, here’s one danger you may not have thought of: Grilling meats has been shown to form cancer-causing substances, according to the American Institute for Cancer Research (AICR). Studies have also demonstrated that one of the possible cancer-causing substances could be reduced when the meat, poultry, or fish has been marinated for at least 30 minutes with a mixture of vinegar, lemon juice, or wine with herbs and spices. “Cooking the meat over a low flame as well as trimming off the fat and flipping it frequently can help reduce the formation of the cancer-causing substances,” says Tracy.

Potato salad

When you see potato salad on a picnic table, you can probably assume that it’s safe to eat, but there’s one instance in which it can become dangerous: when the potatoes are baked ahead of time and then stored in foil. Spores of Clostridium botulinum—the group of bacteria that causes botulism—can survive the potato-baking process. Leaving the cooked potatoes wrapped in foil at room temperature produces perfect conditions for those spores to germinate and grow, and release their deadly toxin. In 1994, an El Paso, Texas Greek restaurant kept baked potatoes at room temperature for several days before using them in a dip; 30 people contracted botulism. Botulism is exceedingly rare, but even still, you’re best off prepping potatoes the same day you plan on making them into a salad.

This article originally appeared on Health.com

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