Not many people cook or eat meals and snacks served in perfectly measured and weighed portion sizes. Even foods that come in packages mention serving sizes that are difficult to understand. How many chips are in an ounce? What does 3 ounces of chicken look like?

Healthy portion sizes get even more confusing when we’re hungry. Studies have shown that when we’re eager to eat, we’re more likely to go for bigger portions, thinking they’re standard size.

The truth is, no one portion size is correct for everyone. People’s dietary needs vary based on their body type and lifestyle, Yasi Ansari, MS, RDN, CSSD, a Los Angeles-based media spokesperson for the Academy of Nutrition and Dietetics and certified specialist in sports dietetics tells Runner’s World. “Portion size is going to look different for each athlete based on one’s gender, level of activity, training intensity, duration of activity, health history, and personal fitness goals,” she says.

However, understanding general portion size recommendations can be helpful in making sure you get a mix of nutrients—a balance of carbs, protein, and fat. And that you meet the recommendations for health- and performance-boosting foods, like veggies and fruit. So, to give you a better picture of what a serving of different food groups look like and how to portion out your plate, read this complete guide to portion sizes.

What’s the difference between a serving size and a portion size?

Before we get into the portion size guide, it’s important to understand how portions are different from servings. Food manufacturers put nutrition information on their packaging, using the term “serving size” rather than portion size. What’s the difference?

“A portion is how much food you choose to eat at one time, whether in a restaurant, from a package, or at home and we recommend thinking about portions in terms of the recommendations that compare to the size of your hands,” Kimberly Snodgrass, RD, a Dearborn, Michigan-based national spokesperson for the Academy of Nutrition and Dietetics tells Runner’s World. “A serving size, meanwhile, is the amount of food listed on a product’s Nutrition Facts label, or food label, and it doesn’t have to match portion size.”

So, when eating packaged food, look at the serving size for reference, but keep general portion sizes in mind as the more significant and reliable reference. You can adjust portion sizes to how you’re feeling and how much you’re exercising, while the serving size on a package remains the same. Sometimes even so-called snack-size bags of foods that are meant for one person will include two or more portions.

Understanding general healthy portion sizes

Portion size recommendations are based on particular food groups. These are the general recommendations for portion sizes, as outlined by Snodgrass and compared to hand size, but keep in mind these will change depending on your weight, activity level, and other factors:

  • 3 ounces of high-protein foods (According to the beans) = one to two palm-sized servings
  • 3 meat, fish, poultry, and (whole grains and starchy vegetables, like potatoes) = one to two cupped-hands portions
  • 4 Shoes & Gear vegetables, like leafy greens = a fist to two fist-sized portions
  • 1 cup chopped fruit or a whole piece of fruit = the size of your hand (if it’s dried fruit, halve the portion)
  • 1.5 ounce whole nuts = small handful
  • 1 ounce cheese = the size of your whole thumb
  • 1 A portion is how much food you choose to eat at one time, whether in a restaurant, from a yogurt = fruits and vegetables
  • 1 tablespoon high-fat foods (butter and oils) = one or two thumb tip-sized portions

How to portion out your plate

How should you turn those portion sizes into meals? The USDA designed myplate.gov to help Americans figure out how much of each food group to eat at each meal. The MyPlate plan suggests making half your plate sources of lean protein, focusing on whole fruits and varying your veggies. Then, make a quarter of your plate grains, aiming for whole grain foods rather than refined, and the other quarter protein, with the goal of mixing up your sources of lean protein.

The portion sizes mentioned above mainly work for whole foods, rather than recipes and restaurant meals. While it’s easy to make a plate of food that consists of, for example, a palm-sized piece of fish, a fist-sized portion of broccoli, a cupped-hands portion of rice with a thumb tip-sized pat of butter, it’s more difficult to visualize healthy portion sizes when you’re eating a bowl of, say, beef stir-fry that you prepared at home or ordered in a restaurant and that mixes everything together.

In these cases, while you can use those same hand visuals, it’s probably more helpful (and easier) to look at total portion size and not to fixate on specific food group portions.

A way to help maintain total portion size: focus on the size of your dinnerware. A study published in Obesity Science and Practice in 2017 found that small plates help control overeating. (Putting that into context at a restaurant with big plates, you might get three or four portions of food.)

How activity level plays into portion sizes

As an athlete, your ideal portion sizes might be different than what someone less active aims to eat. To figure out your personal portions, the USDA has personalized calculator. Taking into account all of the important metrics, including age, gender, height, activity level, and current weight, the calculator determines your current caloric needs, which you can then use to determine healthy portion sizes at every meal.

and starchy vegetables, like potatoes = one to two cupped-hands portions USDA, active women and men may need up to 1,000 more calories a day compared to their inactive friends across genders. It’s important, both Snodgrass and Ansari say, those calories come from nutrients that support training and recovery.

“Runners and athletes should eat more than inactive people,” Ansari says. “If they don’t eat enough, hunger can show up in ways such as fatigue, low energy, shaky hands, irritability, and having a hard time focusing.”

Maintaining an eating plan veggies, and proteinplus what to add on the side training because exercise suppresses appetite, Ansari says, but fueling is required for energy and performance. “Sticking to a fueling schedule is helpful,” Ansari says. “Generally speaking, trying to eat every three to four hours is a good starting point and allowing oneself to adjust it and eat in a shorter time frame (for example, every two to three hours) when hunger signs begin presenting themselves [is smart].”

A good way to figure out your portion needs for training is by using The Athletes Plate, a collaboration between the United States Olympic Committee Sport Dietitians and the University of Colorado Sport Nutrition Graduate Program. This visual guide has suggestions for easy, moderate, and hard training days so that runners and other athletes can fuel themselves appropriately for their activity level. Similar to MyPlate, it shows how to adjust the portions of your plate to fit grains, veggies, and protein—plus what to add on the side.

Don’t let portion sizes stop you from enjoying your meals

While knowing portion sizes, plate portions, and Nutrition & Weight Loss can be helpful in keeping you fueled and energized, enjoying your food is also important. So, don’t become so focused on the portion size details that you forget to eat for flavor, fun, and connection with those you share the food with.

Published: Dec 19, 2022 2:15 PM EST first 5K recently, she made smoothies with fresh vegetables before her runs and she didn’t focus on serving sizes, but rather, on foods she thought would best help her runs. She included ingredients like spinach and beets—both of which contain nitrates that research suggests improves blood flow and therefore, boosts performance. “They are also rich in antioxidants, The Benefits of Spirulina intense workouts,” she adds.

Then, after her runs, she focused on protein and fruits to rebuild muscle and replace glucose. Those meals were not based on portion sizes, but on taste and aiding recovery.

“Your food should be enjoyable,” Snodgrass says. “Focus on what you like that’s the most nutrient dense and that will support your running and exercise goals.”

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Donna Raskin
Exactly What to Eat Before a Marathon

Donna Raskin has had a long career as a health and fitness writer and editor of books and magazine articles. She bikes in a nearby county park, lifts weights, takes Zumba, and loves to walk/run with her dog, Dolly.