Lisa Drayer is a nutritionist, author and CNN health and nutrition contributor.
Let me guess: You’re eating clean, enjoying lots of fruits and vegetables, cutting out meat and are much more plant-based. You’ve also banned bread, cookies and cake from the house. There is just one problem: You can’t seem to stay awake and alert during the day.
On the surface this lifestyle may seem healthy, but it may include some behaviors that are actually zapping you of energy.
“Healthy eating can sometimes turn into something that is not so healthy and can drain you of energy if you are too restricted,” said Yasi Ansari, a registered dietitian nutritionist and Academy of Nutrition and Dietetics spokesperson.
Here are a few ways a so-called “healthy” diet can make you sluggish — and what you can do to get your energy back on track.
Cutting too many calories
“If you are trying to lose weight and you reduce your calories too dramatically, this can leave you without the right amount of energy or fuel that you need to get through the day,” said Elizabeth DeRobertis, a registered dietitian and director of the Nutrition Center at Scarsdale Medical Group, White Plains Hospital.
Food provides the energy you need to stay focused and productive throughout the day. And though sometimes people think if they want to lose weight, they should eat as little as possible, this doesn’t work for the long term, said DeRobertis, the creator of the GPS Weight Loss Program, an online self-paced weight loss program. When someone becomes too restrictive with their intake, metabolism can slow down, and you may feel drained of energy. “You also end up too hungry … and end up overeating as a result,” DeRobertis said.
“If you are feeling low in energy, check in on the energy you’re taking in,” said Melissa Majumdar, an Atlanta-based registered dietitian and certified obesity and weight management specialist. “Start with adding an additional 1 to 2 ounces of lean protein, a half cup of whole grains, or 1 tablespoon of a healthy fat and reanalyze.”
Eating too infrequently
Going too long without eating can also make you feel tired. “Some people experience sleepiness or sluggishness as a sign to eat more instead of the traditional hunger cues,” said Majumdar, who is also the metabolic and bariatric coordinator at Emory University Hospital Midtown. “If two or three hours after a meal you are low in energy, plug in a balanced snack of fiber and protein, like fresh fruit with a handful of nuts or a small bag of edamame.”
“Identifying when your body starts to get hungry can help you better understand how to be most consistent with your nutrition and its timing to ensure your energy is stable throughout the day and you’re supporting your body in meeting its needs,” Ansari said.
Cutting too many carbs
Going low carb can also make you feel lousy. Not only can eating too few carbs make you feel tired and irritable from low blood sugar; it can also lead to dehydration, which can cause fatigue. “For every gram of carbohydrate stored in the body, there is approximately 2 to 3 grams of water retained,” DeRobertis explained. But when someone reduces their carbohydrate intake too dramatically, water is released, and it’s possible to become dehydrated.
“When someone feels a dip in energy in the afternoon, I always think of a plant that is wilted, and in need of water,” DeRobertis said. “When we water the plant, it perks back up. And I picture that is what happens to our cells when we are not well-hydrated enough during the day.”
Cutting carbs, especially cookies and sugary treats, is perfectly fine, but make sure you’re not skimping on fiber-rich carbs, like fruits, vegetables and whole grains.
Not eating a balanced vegetarian diet
Banning animal proteins as part of a vegetarian diet isn’t necessarily unhealthy, but it’s important to be conscious about consuming a balanced intake of all nutrients.
“If someone chooses to eat in a vegetarian or vegan style, but they are not careful about obtaining enough vitamin B12 and iron (from supplements and plant sources), they may end up with anemia and a resulting feeling of fatigue,” DeRobertis explained.
Foods high in iron include beef, iron-fortified cereals, spinach and beans. If you consume plant sources of iron, it’s wise to add some vitamin C to enhance absorption. “An example might be a spinach salad with a small glass of orange juice or a lentil soup with chopped tomatoes,” Ansari said.
Vegans should also be aware of a possible vitamin B12 deficiency. “A B12 deficiency may take years to develop, so supplementing in advance if you don’t eat animal foods like meat, fish, eggs and dairy is key,” Majumdar said. Nutritional yeast can also add some vitamin B12 but would need to be eaten daily to provide enough, Majumdar added.
Eating too many carbs
Having too many carbohydrates in one sitting can also contribute to sluggishness.
Even healthy carbohydrates turn to sugar in the body, and our pancreas, in response, produces insulin, to keep our blood sugar stable.
“If someone has too many carbohydrates in one sitting — even if it’s healthy carbs, like brown rice, beans, sweet potato, whole grain pasta, or quinoa — for some, too many can raise blood sugar, and high blood sugar makes us feel tired and lethargic,” DeRobertis said. (While this often happens among individuals with diabetes, it can happen to anyone who eats too many carbs in one sitting, she said.)
Pay attention to how you feel after different meal combinations, and if you notice that you feel tired after a high-carb meal, consider spacing out your carbohydrates during the day, DeRobertis advised.
Exercising too much
Overexercising can also make you feel tired. “How much is too much depends on the person, other demands in their life, stress levels, overall health and fitness levels, and the types of exercise,” Majumdar said.
Underfueling for a workout can also be a contributor to fatigue. “During exercise, the body typically burns a combination of fat and carbohydrates. If you are not eating enough carbohydrates, it is more difficult to fuel the workout, and if this pattern progresses, the body’s stored carbohydrates, called glycogen, aren’t restocked,” Majumdar said. This can leave you feeling drained, frustrated and demoralized with your workout, according to Majumdar.
“Take inventory of how you feel before and after exercise sessions and consider adding carbohydrates or calories to your intake, or reducing your exercise to keep energy levels balanced,” Majumdar said.
If exercise is eating into sleeping time, this can also impact energy levels. Getting an adequate amount of sleep not only gives you energy, it also helps the body to actively repair muscles and tissues used during exercise, according to Majumdar.