The afternoon meeting, early morning workout, midterm exam or late-night dinner date are all more enjoyable—and successful—with an abundance of energy.

Humans get their energy (calories) from food in the form of protein, carbohydrates and fat. Enzymes and bile break down food components, which are then transported into the cytoplasm and mitochondria of cells, where they are further broken down into adenosine triphosphate (ATP). ATP stores the energy that humans use to do their activities.

Energy on the cellular level translates into human lives with alertness, exercise tolerance and increased calorie expenditure. While food provides energy, zero-calorie natural ingredients can spur energy by influencing the cellular process.

For humans, coffee has been the fuel of choice for centuries, and is still the most popular caffeine delivery device. Years of research on coffee and caffeine have proven they help boost energy. For instance, a 2007 study from Saint Louis University found caffeine, which has no calories, increased the release of ATP by close to 70 percent in rabbits who consumed an equivalent of a human drinking one to two cups of coffee. Combining exercise and caffeine supplementation was more effective for promoting energy use, and led to exercise being perceived as less difficult and more enjoyable than exercise alone in recreationally active participants.

Another study found caffeine ingestion significantly increased energy expenditure in individuals regularly completing rigorous resistance training by 15 percent both before and after exercise compared to placebo.

Tea is another favorite way to get caffeine, and research has shown its benefits to energy. Tea is also filled with health-promoting catechins, a group of flavonoids that has been studied for their effects on energy. Tea consumption was associated with better brain energy, including global cognition, memory, executive function and information processing speed in community-living Chinese older adults. Both black/oolong tea and green tea consumption were associated with better cognitive performance.

Combining caffeine with other natural ingredients, such as capsaicin, ginger, ribose, bitter orange and others has also shown to be a winning energy proposition.

A formula of green tea extract, the botanicals bitter orange (as Advantra Z from Advantra Z Inc.) and guarana, with synephrine (bitter orange’s active ingredient), caffeine and catechin polyphenols, demonstrated increased ATP production from carbohydrate oxidation in overweight, adult males at rest.

Combining D-ribose (as Bioenergy Ribose) with caffeine significantly reduced caffeine usage levels and provided sustained energy for better performance in a mice fatigue model. The D-ribose and caffeine combination was also safer than caffeine alone because D-ribose protected organs from stress caused by caffeine and high-intensity exercise.

A combination of L-carnitine and caffeine promoted fat oxidation, resulting in higher endurance performance in athletes.

Caffeine and phosphatidylserine (PS), a phospholipid membrane component, has also shown energy benefits to the brain. Supplementation increased the number of correct answers and significantly decreased time to answer in a cognitive function and reaction time test following acute exercise stress.

Polyphenols, antioxidants found in plants, boost energy without caffeine. In a study from 2011, rats that consumed aqueous mixtures of 25 mg/d of polyphenols (catachin, chlorogenic acid, ellagic acid and quercetin) showed a significant increase in swimming time, and polyphenols increased the concentration of ATP.

elevATP™, a proprietary combination of a water extract of ancient peat (fossilized plants) and apple extract from FutureCeuticals, caused an increase in blood levels of ATP by 64 percent without increasing oxidative stress in healthy adults.

Capsiatra Dihydrocapsiate is similar to capsaicin—the potent ingredient in hot peppers—but is not at pungent and does not elevate heart rate or blood pressure. It’s known for its ability to help manage weight due to increased resting energy expenditure, but newer studies showed it increases endurance by conserving muscle glycogen stores.

The brain-energy botanical Bacopa monniera (as Synapsa™ from PLT Health Solutions) significantly improved speed of visual information processing, learning rate and memory consolidation and state anxiety compared to placebo, with maximal effects evident after 12 weeks.

Chia, which is rich in omega-3 essential fatty acids (EFAs), was a viable option for enhancing performance for endurance events lasting longer than 90 minutes, and it allowed athletes to decrease their sugar intake, according to a study from 2011.

Other natural ingredients help energize through various mechanisms. During athletic competitions or recreational pursuits, the body's hydration level can become compromised, resulting in lower energy. Glycerol, a sugar alcohol that is absorbed and distributed throughout the intracellular space, has been used to induce hyperhydration to reduce the deleterious effects of dehydration.

Citicoline, a brain chemical that occurs naturally in the body, helps energize the brain. Healthy adult women, aged 40 to 60, who took 250 mg or 500 mg of citicoline, made fewer omission and commission errors in the Continuous Performance Test II (CPT-II), a measure of attentional function, compared to those in a placebo group.

The body uses coenzyme Q10 (CoQ10) to create ATP, which fuels cellular metabolic activity. In the cell, CoQ10’s main role is in the mitochondria, where it helps convert food into energy. CoQ10 improved subjective fatigue sensation and physical performance during fatigue-inducing workload trials.