June/July 2020 Issue

Energy Foods: Lunch and Snack Ideas to Counter the Afternoon Slump
By Ginger Hultin, MS, RDN, CSO
Today’s Dietitian
Vol. 22, No. 6, P. 14

Some clients start their days with a burst of energy that gets them through the first part of the morning. But then something happens shortly after their lunch break. Feelings of fatigue, brain fog, sleepiness, and cravings for caffeine and sugar all seem to set in—a cluster of symptoms commonly known as the “afternoon slump.”1,2

Sluggishness—and, at times, the inability to keep one’s eyes open in front of the computer—often are a result of hormonal changes that occur throughout the day and the body’s natural circadian rhythms. Other culprits include food timing and food choices, hydration status, sleep quality and quantity, and physical activity habits, or lack thereof.2 Studies show that food choices earlier in the day can cause afternoon energy slumps.1-3

For these reasons, it’s important for dietitians to address their clients’ afternoon energy issues by taking a holistic approach. They can perform dietary assessments to uncover what their clients are eating early in the day that’s leading to a dip in afternoon energy, as well as evaluate other lifestyle factors that may be causing the problem.

Caroline Passerrello, MS, RDN, LDN, a spokesperson for the Academy of Nutrition and Dietetics (the Academy) and instructor in the department of sports medicine and nutrition at the University of Pittsburgh, says, “With my clients, when they ask me, ‘What can I eat to have more energy in the afternoon?’ I respond with, ‘Let’s talk about what you are eating for lunch, what you are drinking during the day, how you are sleeping, and what your physical activity looks like on a typical day.’”

Malina Malkani, MS, RDN, CDN, a spokesperson for the Academy and author of Simple & Safe Baby-Led Weaning, says, “Possible culprits of a midafternoon energy slump include sleep habits, age, and even hormones, but the most common cause I see is usually poor food choices at breakfast and/or lunch.”

Foods and Nutrients That Boost Afternoon Energy
Energy has been tough to quantify in the literature, so research on this subject often focuses on the desire to continue eating, food cravings, and the type of snacks people seek. However, research demonstrates a connection between energy and satiety. The correlation may be due to the fact that people who experience an afternoon slump seek short-term energy boosters such as caffeine or sugar, which fail to sustain energy, while neglecting foods considered more satiating and nutrient dense. Specifically, studies show that protein-containing foods and those high in fiber, in particular,are more filling and therefore can help stave off hunger.

Other studies have shown a connection between protein and carbohydrate intake and their effects on mood, which could impact a client’s mental state after eating. What’s more, research shows that the neurotransmitter 5-hydroxytryptamine, or serotonin, plays an integral role in depression, mood regulation, and the sleep/wake cycle. Both carbohydrates and branched-chain amino acids can play a part in increasing serotonin, which researchers hypothesize may help reduce mental fatigue.4

Passerrello recommends including foods from at least three food groups, such as lean proteins, unsaturated fats, and complex carbohydrates, at each meal and snack so the body can digest and absorb the nutrients over a sustained period of time and energy levels can remain balanced.

Previous research on high-protein breakfasts and their positive impact on satiety and weight management suggests that high-protein breakfasts may lead to more healthful lunch choices. Some studies have found that participants who ate 30 g protein at breakfast had better satiety levels through increased fullness, greater concentrations of the satiety-related hormone peptide YY, reduced food cravings, and less unhealthful snacking in the evening when compared with those who either skipped breakfast or consumed a breakfast with less protein (13 g).2,3

Other research has shown that eating eggs for breakfast vs eating a bagel caused participants to experience greater feelings of satiety later in the day.5 It’s believed that protein helps stabilize blood sugar, preventing its dip after digestion and the decreased energy that follows. When people are more satiated, they’re better able to go longer between meals without needing to refuel.

A study on 32 adults randomly assigned to afternoon snack groups for six days found that those who consumed hummus and pretzels three hours after lunch experienced a reduction in hunger, desire to eat, and subsequent food consumption for the remainder of the afternoon compared with the no-snack group. Participants in the hummus snack group also experienced a greater decrease in hunger and desire to eat than those in the granola bar snack group and no-snack group.1

The hummus snack also caused smaller reductions in afternoon alertness when compared with the no-snack group. (Note that these participants were assigned a standardized breakfast, lunch, and dinner during the study.) Though this study was small and industry funded, the results reflect what other researchers have found.1

Enriched Pasta
In a small study of 22 women, consumption of high-protein, high-fiber pasta was compared with a control pasta (a “standard commercial” variety) to determine satiety and potential for afternoon snacking. Researchers found that the high-protein, high-fiber pasta significantly increased satiety and significantly reduced energy intake of snacks in the afternoon.6

Enjoying pasta that’s higher in both protein and fiber for lunch also may help with satiety and weight management. Pasta made from beans and lentils meets the criteria for high protein and high fiber and is a versatile food that easily can be incorporated into a weekly lunch meal plan. If clients feel more satiated after lunch, this reduces their desire to snack on unhealthful foods, boosting blood sugar and subsequent energy.

Studies on almonds and pistachios as snacks have shown positive outcomes for satiety in adults. Almonds have been found to lower postprandial blood glucose and reduce hunger and desire to eat, which may help prevent the afternoon slump and the mindless snacking that sometimes accompanies it to boost energy.7,8 Greater satiety helps balance blood sugar and enhances mental focus on other tasks. Pistachios have been shown to promote glycemic control and improve satiety, again making them a potentially healthful afternoon snack or an addition to the lunch meal.9

Moreover, a study of 17,444 children and adults found that those who replaced typical American snacks high in saturated fat, sodium, and added sugars with tree nuts or almonds were better able to meet the Healthy Eating Index 2010 guidelines for unsaturated fats, plant omega-3 fats, fiber, magnesium, and potassium.8

Peanuts may have a similar effect on satiety. In another study of 61 middle-aged and older adults, adding peanuts to the diet decreased intake of savory snacks among men and sweet snacks among women. Due to peanuts’ high caloric content, the researchers recommend they be substituted for less healthful snacks rather than added to the diet.10

Similar to other high-protein options for breakfast, lunch, and afternoon snacks, research has been conducted on high-protein Greek yogurt, which helps with appetite control and satiety and delays subsequent eating when compared with lower-protein yogurt. Including yogurt at lunch or as a snack may stabilize energy later in the day.11

Energy Thieves
Just as eating certain foods earlier in the day may boost afternoon energy levels, other foods may increase the desire to munch on unhealthful foods and worsen energy slumps.

“Heavily processed foods and refined carbohydrates like candy, soda, and products made with refined white flour are typically digested quickly, which can lead to the spikes and dips in blood sugar levels that tend to fuel those postlunch slumps,” Malkani says. “Choosing an apple and a handful of nuts instead of a donut provides the body with a combination of protein, fat, and fiber-rich carbohydrates that can mean the difference between a high-energy and a low-energy afternoon.”

Midday snacks and foods for lunch that reduce rapid spikes and dips in blood sugar are the foods dietitians should be discussing with clients.

Added Sugars
Clients may find themselves craving cookies, candy bars, or soda in the afternoon, but these foods can cause an energy crash. Beverages that contain added sugars can be a major issue, Passerrello says, noting that “too much sugar, alcohol, and caffeinated beverages can negatively impact our energy in the long run; focus on decaffeinated and unsweetened beverages.”

Macronutrient Imbalance at Lunch
A small study of 12 subjects compared the satiating effects of three types of liquid lunches: high carbohydrate, high-protein, and one containing an equal mixture of the first two formulations. Researchers found that the female participants who consumed the high-carbohydrate lunch ate 31% more calories at dinner than those who consumed the high-protein lunch, and 20% more calories at dinner than those who ate the balanced lunch.12

These findings suggest that a high-protein and a more balanced lunch of protein and carbohydrates may reduce hunger later in the day and thereby stabilize energy levels through the afternoon.

Balanced Lunch Ideas
Clients who want to consume lunches that will provide longer stretches of energy throughout the day should choose a balance of lean proteins, healthful fats, and fiber-rich carbohydrates, Malkani says. Such a combination will help slow the rate of digestion, stabilize blood sugar levels, and prevent postmeal fatigue. Malkani’s favorite food choices include the following:

• lettuce-based salads with a variety of veggies (eg, carrots, cucumbers, tomatoes, and green beans), topped with chickpeas, avocado dressing, and a sprinkle of sunflower seeds;
• whole grain pita pockets stuffed with hummus, lettuce, tomato, and onion;
• bean burritos filled with corn, onion, spinach, zucchini, and bell peppers and topped with guacamole; and
• dairy or soy yogurt mixed with chopped fruit, nuts, and seeds.

Passerrello recommends Mason jar salads with olive oil and balsamic dressing on the bottom, then a layer of chickpeas, roasted beets, artichoke hearts, kalamata olives, red peppers, carrots, feta cheese, cooked quinoa, and spring mix greens.

Other balanced lunch choices include the following:

• one protein option (eg, meat, seafood, nut butter, tofu, or tempeh) on whole wheat bread;
• one cup of soup (eg, vegetable, minestrone, lentil); and
• avocado spread on whole grain bread or crackers with an egg and/or hemp seeds.

Recommendations for RDs
Counseling patients on how to prepare balanced meals for sustained energy throughout the day requires active listening, discussions about current meal patterns and preferences, and a full lifestyle assessment. In addition to energy-sustaining foods, they may need an afternoon break that includes taking a short walk outside for some fresh air or using a breathing or meditation app to recharge mentally or spiritually.

If clients need a variety of lunchtime meal choices, dietitians can use motivational interviewing skills to gauge their readiness for change. Discuss clients’ ideas and what’s worked for them in the past. If they’re ready for action, ask permission to educate them and whether they’d like some balanced meal and snack ideas. Focus on complex, whole grain carbohydrates and fiber- and protein-rich foods for breakfast, lunch, and afternoon snacks.

— Ginger Hultin, MS, RDN, CSO, is a nutrition and health writer based in Seattle. She’s past chair of the Vegetarian Nutrition Dietetic Practice Group, past president of the Chicago Academy of Nutrition and Dietetics, a spokesperson for the Academy of Nutrition and Dietetics, and owner of concierge nutrition practice Champagne Nutrition LLC.


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