Energy Bars and Warfarin

Publication Date: 
Thu, 10/01/2015
By: Alere Staff

  With today’s busy lifestyles, we often either have no time to prepare a meal or fail to eat as we should. In an effort to eat healthy, many people will choose to replace meals with, or snack on, the endless variety of energy bars that can be found on store shelves. These bars can provide people with a better choice for a quick meal or snack in moderation. For those on warfarin therapy, these bars need to be chosen carefully as they can impact and cause INR changes.

Besides ease and convenience, what are some of the more common reasons people reach for energy bars?

  • Many energy bars contain a combination of both simple and complex carbohydrates along with various proteins, fats, fiber, vitamins and minerals.1
  • The primary source of protein in many energy bars comes from milk while the fiber comes from whole grains and oats.1
  • If people are feeling a bit drained, some bars contain herbs like ginseng and guarana that can offer an additional energy boost.1
  • Energy bars can be a good snack before a workout as some include minerals like sodium and potassium phosphate that increase a body’s ability to consume oxygen and can help in reducing lactic acid buildup in muscles while exercising.1

No two bars provide the same nutritional profile and each brand offers a different size of bar, ranging from one ounce to more than five ounces. Many have a calorie count ranging from 100 to 300 as well as multiple flavors and textures.1,2 While many may sound like a treat, it is important as a patient on warfarin to read the label of the energy bar you have chosen to eat. In addition to the various herbs that these bars may contain, knowing the vitamin K component of each bar is a necessity as vitamin K content and herbal supplements can affect INR.3

As always it is best to talk to your healthcare provider when making changes to your daily dietary intake. Review the bars you like with them. A healthy diet of whole foods, fruits and vegetables is always the best choice but energy bars can provide a healthy alternative to other snacks or when missing a meal when chosen wisely. 

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  1. Cintado, A. Energy Bars: An Athlete’s Friend or Foe? Vanderbilt University Health Psychology Department. Retrieved from the website:
  2. Robinson, K.R. PharmD, BCPS, et al. Food and Lifestyle Interactions with Warfarin. 2012. Retrieved from the website:
  3. Nutescu, E.A. et al. Cardiovascular and Renal: Warfarin and Its Interactions with Foods, Herbs and Other Dietary Supplements.Expert Opinion Drug Safety. 2006. 5(3). Retrieved from website: