Do You Have a Leaky Gut or Need a Probiotic Supplement? | STACK

Become a Better Athlete. Sign Up for our FREE Newsletter.

Do You Need a Probiotic Supplement?

March 19, 2013 | Gary Mullen

Must See Nutrition Videos

Contrary to what Erin Andrews' latest probiotic commercial would lead you to believe, there is nothing "cute" about your gut (i.e., your digestive system). Fortunately, the growing popularity of probiotic supplements (see STACK's article on the Best Probiotic Supplements) has focused public and medical attention on the importance of maintaining a healthy gut. This is a step in the right direction, because everyone, especially athletes, needs a healthy gut for optimum health.

What often gets lost in the conversation is the true complexity of the gut. It contains healthy bacteria that aid in digestion and immune function. It's not as cut and dry as we're led to believe. Everything from exercise to supplements and nutrition can alter how your gut functions daily. Although many people seek to protect themselves with a probiotic supplement (containing healthy bacteria), supplements are often unnecessary for a healthy gut. Sometimes all we need is a simple adjustment to our diet and lifestyle to rid ourselves of a leaky gut and subsequent illness.

What is a leaky gut?

A leaky gut is damage to the intestinal lining that alters the body's ability to protect its internal environment. Unhealthy bacteria and toxins, incompletely digested proteins and fats, and waste not normally processed may "leak" out of the intestines into the bloodstream.

How do I know if I have a leaky gut?

Symptoms include abdominal bloating, excessive gas and cramps, fatigue, food sensitivities, joint pain, skin rashes and autoimmunity. Physicians diagnose gut problems indirectly via a blood test. The blood contains markers that provide cues of gut leakiness, potentially indicating damage. Such markers include:

  • Protein carbonyl (CO) groups: marker of oxidative stress
  • TNF-alpha: mediator of the acute phase of inflammation
  • IL-6: proinflammatory cytokine
  • Zonolin: sign of impaired junctions in the gut (Fasano, 2011); simply put, the higher the zonolin, the leakier the gut!

What Causes Gut Leakiness?

  • Intense exercise: Sorry all you exercise fanatics, but intense exercise increases intestinal permeability (Gareau 2010).
  • Use of nonsteroidal anti-inflammatory drugs (NSAIDs) increases gut permeability (van Wijck 2012) (Read more about NSAIDs before training).
  • Lack of bacterial exposure: Obsessive cleanliness can actually increase the incidence of certain diseases—like asthma, obesity, allergies and cancer. The condition can even in newborns, as the decreasing incidence of breast feeding and the increasing number of Cesarean sections are reducing infants' exposure to healthy bacteria. Researchers have  found that infants delivered by Cesarean section lack a specific group of bacteria found in infants delivered vaginally, even if they were breastfed. Infants strictly formula-fed, compared with babies who are exclusively or partially breastfed, also had significant differences in their gut bacteria (Azad 2013). Their lack of bacterial exposure prevents them from having the healthy bacteria they need to maintain a healthy gut and fight against unhealthy bacteria that may enter their systems through the environment.

What Helps Gut Leakiness?

Many of those seeking the best probiotic supplement probably think they help a leaky gut. Unfortunately, money spent on expensive supplements is likely wasted, as Lamprech (2012) demonstrated. After 14 weeks of probiotic treatment, zonolin was reduced by only 30 percent. This suggests that probiotic supplements are not the solution for preventing the contributors to a leaky gut.

A safe bet is a combination of pro- and pre-biotics, which are luckily found in many foods:

  • Fermented foods (sauerkraut and kimchi for example)
  • Mushrooms
  • Leeks
  • Artichokes
  • Milk and yogurt
  • Onions
  • Asparagus
  • Bananas


Azad MB, Konya T, Maughan H, Guttman DS, Field CJ, Chari RS, Sears MR, Becker AB, Scott JA, Kozyrskyj AL. "Gut microbiota of healthy Canadian infants: profiles by mode of delivery and infant diet at 4 months." CMAJ. 2013 Feb 11. [Epub ahead of print]

Fasano A. "Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer." Physiol Rev 2011, 91:151-175.

Gareau M.G, Sherman P.M., Walker, W.A. "Probiotics and the gut microbiota in intestinal health and disease." Nat. Rev. Gastroenterol. Hepatol. Sept 2010, 7:503-514. doi:10.1038/nrgastro.2010.117.

Lamprecht M, Bogner S, Schippinger G, Steinbauer K, Fankhauser F, Hallstroem S, Schuetz B, Greilberger JF. "Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial." J Int Soc Sports Nutr. 2012 Sep 20;9(1):45.

Wroblewska M, Brzuzan L, Jaroslawska J, Zdunczyk Z. "Effect of buckwheat sprouts and groats on the antioxidant potential of blood and caecal parameters in rats." Int J Vitam Nutr Res. 2011 Sep;81(5):286-94.

van Wijck K, Lenaerts K, Grootjans J, Wijnands KA, Poeze M, van Loon LJ, Dejong CH, Buurman WA. "Physiology and pathophysiology of splanchnic hypoperfusion and intestinal injury during exercise: strategies for evaluation and  prevention." Am J Physiol Gastrointest Liver Physiol. 2012 Jul 15;303(2):G155-68. Epub 2012 Apr 19. Review.

G. John Mullen
- G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California, where he served as a clinical research assistant investigating adolescent...
G. John Mullen
- G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California, where he served as a clinical research assistant investigating adolescent...

Featured Videos

Quest for the Ring: Duke University Views: 70,557
Path to the Pros 2015: The Journey Begins Views: 23,946
Quest for the Ring: University of Kentucky Views: 78,399
Load More


STACK Fitness

Everything you need to be fitter than ever

STACK Conditioning

Sport-specific conditioning programs

Coaches and Trainers

Tips and advice for coaches and trainers


Latest issues of STACK Magazine


Women's sports workout, nutrition and lifestyle advice


Gaming, entertainment and tech news

Basic Training

Military-style training for athletes


Find the latest news relevant to athletes

More Cool Stuff You'll Like

This Just In: Boost Your Workout With Peppermint

Fuel for Thought: Gels, Bloks and Beans

The Best Post-Workout Supplements and Nutrition

4 Creatine Myths Exposed

5 Rules You Must Know Before Taking a Fish Oil Supplement

L.A. Galaxy's Safe Supplementation for Soccer Players

HGH Use Among Teens on the Rise, According to Survey

The 6 Most Promising Weight-Loss Supplements

The Powerful Health Benefits of Turmeric

3 Supplements to Boost On-Ice Performance

Demystifying Popular Smoothie Boosters

Creatine Supplements: Benefits, Concerns, Types and Dosage

The Truth About Muscle-Enhancing Supplements

4 Best Supplements for Football Players

Should I Take Creatine?

Soy vs. Whey Protein

3 Reasons Why You Should Take a Fish Oil Supplement

Ask the Experts: Is Caffeine Safe for Athletes?

2 Safe Pre-Workout Supplements

Blueberry Supplements: Better Than Actual Blueberries?

Can Baking Soda Improve Your Training Gains?

4 Muscle-Building Supplements That Don't Work

How to Select a Healthy Protein Bar

The One Thing You Need to Do to Build Muscle

The 5 Essential Sports Supplements

The Best Time to Consume Creatine

Use Sodium Bicarbonate to Get More Out of Creatine

Workout Supplements: Do You Really Need Them?

7 Fiber Supplements: More Than Just For Weight Loss

Why Creatine Is the Best Sports Supplement

ZMA: Is This Mysterious Supplement Right for You?

7 Sketchy Marketing Phrases Used By Supplement Companies

Do Athletes Need Zinc Supplements?

Make Sure You're Getting Enough Calcium

EXOS Launches New Line of Supplements

What's Missing From the Female Athlete's Diet, Part 2: Iron

7 Rules That Would End PED Use in Baseball Immediately

6 Supplements That Power Quality Workouts

Why You Can't Ignore Pre- and Post-Workout Nutrition

Should You Be Taking BCAAs?

3 Tips on Choosing the Best Post-Workout Creatine

The Positive Side Effects of Creatine (Besides Building Muscle)

Iodine: An Overlooked Essential Mineral for Female Athletes

DHEA Supplements: Should You Take Them?

Why You Need Vitamin D in Your Diet

Powder Hour: Is It Time to Add Protein Powder to Your Diet?