“Eat more delicious whole-food plants at every meal and snack,” said Debra Wein, chief executive of Wellness Workdays. (Istockphoto)

This month, I was one of roughly 10,000 registered dietitian nutritionists who came together in Nashville for the annual Academy of Nutrition and Dietetics’ Food and Nutrition Conference. I couldn’t resist tapping the wealth of health-focused expertise around me, so I asked several of the most prominent dietitians this question: What is the one change a person can make that would most improve his or her health and well-being? This is what they wrote:

Change your mind-set

“Ask yourself why — ‘Why am I making these diet, exercise and lifestyle changes?’ Finding the true purpose — whether it’s for your physical health or other goals for personal success — identifying your motivation is like a light switch going on and provides the inner strength and inspiration needed to maintain healthy habits over the long haul.”

— Carolyn O’Neil, author of “The Slim Down South Cookbook: Eating Well and Living Healthy in the Land of Biscuits and Bacon”

“Always have a positive attitude. Being healthier is something every one of us can do, whether it’s [resolving] to get an hour more sleep each night, cook dinner twice a week, or drink more water. Instead of dragging your feet and thinking that being healthier is something you have to do, make it positive so it’s something you really want to do.”

— Toby Amidor, author of “The Greek Yogurt Kitchen: More Than 130 Delicious, Healthy Recipes for Every Meal of the Day”

Make breakfast count

“Start your day off with a healthy breakfast. It sets the tone for the day. Be sure to add a source of protein — eggs, nut butters, yogurt parfait, or milk — to keep you fuller longer.”

— Janet Helm, dietitian and blogger at Nutrition Unplugged

“There may be something to the old adage to eat breakfast like a king, lunch like a prince, and dinner like a pauper for those trying to lose weight. Some studies suggest that flipping breakfast and dinner to make breakfast the biggest meal of the day may help you flip the numbers on the bathroom scale. The secret may lie in the body’s circadian rhythms, which are physical, mental and behavioral changes in the body and can influence hormone release and other bodily functions.”

— Joan Salge Blake, clinical associate professor at Boston University and author of “Nutrition & You”

Eat plants

“Have a beautiful and colorful salad with most dinners and build it according to the rainbow — think tomatoes, carrots, peppers, spinach or leafy greens, and eggplant. Save time by choosing pre-washed lettuce, cut-up carrots, mini cucumbers, pepper slices and cherry tomatoes. Feeling fancy? Add in some nuts, berries or chia seeds for a little crunch. Enjoy!”

— Debra Wein, chief executive of Wellness Workdays

“Eat more delicious whole-food plants at every meal and snack. Fruits, vegetables, whole grains, nuts and seeds are packed with nutrients and contain satisfying fiber that is good for digestion, disease prevention and sustained energy. No matter what’s on your ‘to-do’ list or what else you’re eating, enjoying these foods regularly help fill you up and keep calories in check.”

— Michelle Dudash, Le Cordon Bleu-certified chef and columnist of DishWithDudash.com

Eat less, enjoy more

“Most of my clients would prefer to eat the foods they love, but eat less of them, rather than to cut out their favorites and feel deprived. Eating less, eating slowly and eating mindfully could help you appreciate the texture, temperature, taste and aroma of the food you enjoy. Smaller portions can also make you feel better physically by preventing the gastrointestinal upset that often follows excessive indulging.”

— Bonnie Taub-Dix, owner of BetterThanDieting.com and author of “Read It Before You Eat It”

Be choosy

“We make more than 200 decisions daily related to food and healthy behaviors. One decision that has served me well is ‘If you don’t love it, don’t eat it.’  Countless times, people eat foods that are mediocre simply because the food is there and available. Becoming more discerning and pickier about choosing foods that are delicious and nutritious takes a concerted effort that will pay you back in spades.  Be picky, be choosy and only eat foods that you love — and try to make those foods ones that are rich in nutrients to make your calories count.”

— Kathleen M. Zelman, director of nutrition for WebMD

Get cooking

“Food should be appreciated and celebrated, not fast-and-furious drive-through meals that are eaten in the blink of an eye. By enjoying a home-cooked meal, you will naturally eat a smaller portion and consume less sodium, all while spending more quality family time together, which research positively shows is associated with overall healthier eating habits. So, let’s get cooking . . . you’ll be glad you did.”

— Elisabeth D’Alto, RD, LDN; Maryland Academy of Nutrition & Dietetics state media representative

“The single thing you can do for better health and well-being is to cook with your kids. Teaching a child how to slice an apple, peel a carrot or create a veggie omelet from scratch fosters confidence in the kitchen, a willingness to try new (and nutritious!) foods and prepares [children] for the future when making meals will become their responsibility. Whenever I ask the moms in my online community how they get their picky eaters to try new foods, the No. 1 response they always give is ‘We cook together.’ ”

— Liz Weiss, Meal Makeover Moms’ kitchen blogger and co-host of the podcast “Cooking With the Moms”

Move more

“Move more. You don’t have to join a fancy gym or commit to crazy group classes (unless you want to) — simply find something that you enjoy doing on a regular basis. Physical activity can be great for your muscles and bones, but especially your mind. The better you feel mentally, the more likely you are to take better care of yourself overall.”

— Keri Gans, author of “The Small Change Diet”

Get enough sleep

“Want to slim down? Make sure you get enough sleep. A review study that looked at 36 studies on sleep and weight gain found short sleep duration was independently linked to weight gain. Another study found that restricting sleep even for a few nights makes you hungrier, more likely to have food cravings and increases your calorie consumption — the perfect recipe for weight gain. Even one night’s poor sleep made people consume more than 500 extra calories the next day.”

— Patricia Bannan, author of “Eat Right When Time Is Tight”

“Even if you eat a near-perfect diet you’re shortchanging your health and well-being in a major way by not regularly getting adequate sleep. That’s seven to eight hours a night for adults. Sleep can help to heal and repair your heart and blood vessels, manage normal blood sugar and maintain a healthy balance of the hormones associated with hunger. If you bottled up sleep, it would be a ‘magic potion’ for health!”

— Jackie Newgent, culinary nutritionist and author of “The All-Natural Diabetes Cookbook”

Krieger is a registered dietitian, nutritionist and author. She blogs and offers a biweekly newsletter at www.elliekrieger.com. She also writes weekly Nourish recipes in The Washington Post’s Food section.

^ Chat Nov. 5 at 1 p.m. Join Krieger for a live Q&A about healthful eating.