Does Your Energy Drink Add to Holiday Fatigue?

Dr. Robert Portman

Everyone feels tired around the holidays. Shopping, family obligations, parties, overeating and lack of sleep can quickly drain your energy stores.  Polls have shown that 68% of Americans experience greater fatigue over the holidays.  It’s also not surprising that during the holidays caffeine consumption increases.


Caffeine’s beneficial effects include increasing energy, reducing fatigue and improving alertness and mental focus.  Caffeine is an effective energy boost that can get you through a hard day of shopping or a work day following a party night and, if you are disciplined about your exercise during the holidays, help you work out harder and longer. With all of these benefits, a caffeinated energy drink or shot should be just what the doctor ordered.


Unfortunately, in their efforts to create a marketing advantage, energy drink and shot manufacturers add a whole host of vitamins and other ingredients to caffeine.  Many of these ingredients, such as vitamin B6, have neither a positive nor negative effect. However, two ingredients, niacin and taurine, that are found in most energy products, may actually make you more fatigued, especially when taken in combination with caffeine.


Studies have shown that taurine blunts the effects of caffeine.  It does this by activating specific receptors in the brain responsible for decreasing mental alertness.  Whereas caffeine makes you more alert and gives you more energy, taurine has the opposite effect, it makes you more tired and sleepy. Researchers suggest that taurine may be responsible for the “energy crash” that’s been reported after consuming an energy shot.


The other ingredient found in many energy drinks and shots is niacin, also called Vitamin B3.  No study has shown that niacin raises energy levels. However studies do show that niacin decreases endurance. Here’s why. Whenever we need energy for extended periods of time, our body increases the breakdown of fat to provide fuel for working muscles. Niacin inhibits the breakdown of fat thereby depriving muscles of a much needed energy source. The result- you become tired faster.


If you want to get the full benefits of caffeine, look at the label on your energy product. Be sure to select a product that does not contain niacin or taurine.  Even better, chose an energy product that has a small amount of carbohydrate and protein.  Whereas taurine and niacin decrease the effectiveness of caffeine, small amounts of carbohydrate and protein significantly enhance it.


This was demonstrated in a recent study from Montana State University where sports science researchers compared two commercially available energy shots, one that contained taurine and niacin and another that did not contain either of those ingredients but did contain a small amount of carbohydrate and protein.  The results were dramatic.  The caffeine/carbohydrate/protein combination was shown to be 200% more effective than the caffeine/taurine/niacin combination in extending energy levels, improving alertness and mental focus. In fact the caffeine/taurine/niacin combination was shown to be no more effective than flavored water.


The bottom line – as long as you are not allergic or hypersensitive, caffeinated drinks and shots are great tools to get you through the energy-depleting holiday season. Just make sure that your energy drink or shot doesn’t contain ingredients that increase holiday fatigue.



Dr. Robert Portman is a well-known exercise scientist and author of Nutrient Timing and The Performance Zone.  His latest book is Hardwired for Fitness.