Eating for Energy: 3 Nutrients That Can Put a Pep in Your Step

If you struggle with sleepiness during the day, you're certainly not alone. According to the Centers for Disease Control and Prevention (CDC), more than 15 percent of U.S. women and 10 percent of men often feel either very tired or exhausted.

It's little wonder, then, that energy drink consumption is on the rise. According to a study published June 2019 in the American Journal of Preventive Medicine, more and more adolescents, young adults and middle-aged adults are drinking these beverages on a regular basis.

The problem? Along with a temporary energy boost, these drinks come with several potential drawbacks, including increasing your risk for obesity and cardiovascular issues.

If you often find yourself reaching for a sugary, caffeinated fix, you may want to take a good look at the nutrients you're taking in — or not taking in. B-complex vitamins, vitamin D and the mineral iron have all proven effective in helping to stave off fatigue and promote healthy energy levels, so it's a good idea to make sure you're getting the recommended daily amounts.

Whether you get these nutrients through food or supplements, here's a look at the role each plays in the body, and how to tell if you should seek out a supplement.

What They Do: B-complex vitamins refers to a group of eight different nutrients: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate or folic acid) and B12 (cobalamin).

These essential vitamins assist the body in converting food into fuel. In addition, the B group helps form red blood cells, which are used to deliver oxygen throughout the body.

While each B vitamin has its own function — for example, the body needs vitamin B1 to produce adenosine triphosphate (ATP), a substance required by every cell in the body for energy — they often work together in the body, so it's best to consume all of them in the proper amounts to ensure they're most effective.

Read more: Are Vitamin B12 Pills Good for Weight Loss?

How Much You Need: According to the National Institutes of Health (NIH)'s Office of Dietary Supplements, the following daily amounts of B vitamins — in milligrams (mg) or micrograms (mcg) — are recommended:

• B1: 1.2 mg for males; 1.1 mg for females
• B2: 1.3 mg for males; 1.1 mg for females
• B3: 16 mg for males; 14 mg for females
• B5: 5 mg for all adults
• B6: 1.3 mg for males; 1.5 mg for females
• B7: 30 mcg for all adults
• B9: 400 mcg for all adults
• B12: 2.4 mcg for all adults

Where to Get Them: According to MyFoodData.com, which gathers information from the U.S. Department of Agriculture's database, the foods highest in vitamin B include fish and shellfish, meats, poultry, nuts and fortified products, such as breakfast cereals and certain milks. Biotin (B7) and riboflavin (B2) are both found in eggs, while leafy greens such as spinach and collard greens are wise picks for folate (B9). B12, however, is not found in plants—it must be obtained from animal products, like meat, eggs, poultry, dairy, fish and shellfish.

Read more: Foods That Give You All the Benefits of B Vitamins

Who Should Supplement: The NIH's Office of Dietary Supplements notes that B12 especially can help boost energy and improve endurance. And a deficiency in this nutrient is characterized by fatigue and weakness.

Unfortunately, between 5 and 15 percent of adults are deficient in vitamin B12, according to the Mayo Clinic. Those who may be at a higher risk for deficiency include older adults, people with celiac disease or Crohn's disease, or those who take certain medications, including the diabetes drug metformin and some drugs used to treat reflux or other gastrointestinal problems. If you think you might be deficient, talk to your doctor about which supplements might work best for you.

According to the Academy of Nutrition and Dietetics, vegans and vegetarians who don't eat meat, eggs or much dairy may also want to consider taking a B-complex supplement, although they can find B12 in nutritional yeast, fortified soy milk and soy-based meats, breakfast cereals and some fortified granola bars.

What It Does: You may know that vitamin D helps your body absorb calcium and plays a critical role in maintaining healthy bones. But, according to the Mayo Clinic, it also helps keep your muscles, nerves and immune system in tip-top shape. And there's a growing body of research that suggests the nutrient is tied to how energetic we feel. A study published in August 2014 in the North American Journal of Medical Sciences, for example, found that adults who had fatigue and were deficient in vitamin D reported higher energy levels after being treated with the nutrient for five weeks. A similar study, which appeared in the journal Medicine in December 2016, found a similar effect after four weeks.

How Much You Need: Adults younger than 70 should aim for 600 IU of vitamin D daily, per the Mayo Clinic, while those older than 70 should aim for 800 IU. Keep in mind, though, that between 1,000 and 2,000 IU is considered safe.

Read more: 3 Fast Ways to Bring Up Your Vitamin D-3 Levels

Where to Get It: Your body naturally produces vitamin D when it's exposed to sunlight. When it comes to foods, there are just a few that naturally contain substantial amounts of the vitamin, according to MyFoodData.com, including fatty fish like tuna, salmon, herring, mackerel and sardines, as well as fish liver oils and egg yolks. For most people, however, fortified foods like some breakfast cereals, milk, yogurt, tofu and orange juice are a more palatable source of the nutrient.

Who Should Supplement: According to a paper published June 2018 in the journal Cureus, about 40 percent of the population is vitamin D-deficient. Because there are limited ways to get this nutrient through food sources, the Mayo Clinic suggests that adults who are deficient might benefit from taking a supplement.

Read more: How Vitamin D Supplements Are Linked to Excessive Urination

What It Does: The mineral iron is an essential part of hemoglobin, the substance in the blood that carries oxygen to the rest of the body. It's also a component of myoglobin, a protein that sends oxygen into the muscles, per the NIH's Office of Dietary Supplements. Iron is necessary for growth and development, especially in kids and adolescents, according to the Mayo Clinic.

Your body stores the iron it doesn't use, but if these stores dip too low, not enough red blood cells can be made to carry oxygen efficiently. In this case, according to the Academy of Nutrition and Dietetics, you would develop a condition called iron deficiency anemia, which is marked by fatigue and weakness.

How Much You Need: According to the Institute of Medicine of the National Academies, adult women older than 51 and all adult men need 8 milligrams of iron daily, while women ages 19 to 50 require 18 milligrams per day. Note that women who are pregnant or breastfeeding have different nutritional needs.

Where to Get It: There are two types if dietary iron: heme and non-heme. Heme iron is easily absorbed by the body and the best source of iron for people who are lacking in this mineral, according to the Iron Disorders Institute. Heme iron is found in meat, and red meat is an especially good source.

Non-heme iron must be changed by the body before it can be absorbed, so it is a slightly less efficient source of the mineral. However, non-heme iron accounts for the majority of iron we consume, according to the Academy of Nutrition and Dietetics. It can be found in meats as well as grains such as rice, oats and wheat, and in fortified foods. Other sources include lentils, spinach and white beans.

Read more: The Best Types of Iron Supplements if Iron Upsets Your Stomach

Who Should Supplement: Most people in the U.S. get adequate amounts of iron through their diet, according to the Mayo Clinic, but adults who may be at risk for iron deficiency include pregnant women, women with abnormally heavy menstrual bleeding, frequent blood donors and those who have gastrointestinal disorders such as celiac disease or inflammatory bowel disease.

If you believe you may have an iron deficiency, talk to your doctor or health care provider about whether a supplement may be the right move for you.

Read more: How Much Is Too Much Iron Supplement?