Learn the FACTS about your nutrition as well as myths around common and popular food FADS.
October 19, 2017

Food fact or fiction?

During the course of our lives we are exposed to a lot of advice on nutrition and health. Some of this advice is from reputable, researched sources, such as scientifically reviewed medical and nutrition investigations and publications. But other resources are less consistently reliable: ‘pop’ culture- actresses and models; celebrity chefs; celebrity fitness trainers; the diet and weight loss industry; or food manufacturers or sectors in the food industry.

This large amount of information can make it confusing when selecting a nutrition plan to follow for your health and on-court performance. Read more to learn the FACTS about your nutrition fundamentals as well as myths around common and popular food FADS (fashions) so you can make smart, healthy choices about food.

Allergy or intolerance?

One of the most recent discussions about the athletic diet is that following a gluten-free diet (eliminating food sources with gluten) can optimize performance and health for athletes. This is true if you have a genuine food allergy or intolerance to gluten. However, those who adopt the fashion and follow the restricted diet without proper testing may be harming their health and performance. It is important to be informed what the difference between a gluten allergy and intolerance is; utilize the correct diagnostic criteria and perform the recommended treatment plan.

A food allergy is the body’s adverse response to a particular food or ingredient, often a protein such as gluten. An allergy:

  • Is always accompanied by a negative immune response that generally involves an antibody, which is a protein produced by the immune system that detects harmful substances in the body known as IgE. With an allergy, these antibodies mistakenly identify a substance (nuts, shell fish, gluten, etc…) as harmful when it is not.
  • Can cause a number of negative body responses, such as: bloating, diarrhea, stomach cramps, difficulty breathing, skin reaction (rash, itching, hives, etc…), fatigue and pain.

A food intolerance or sensitivity is an adverse reaction that does not involve the immune system, to foods or to food additives, such as colorants, artificial sweeteners, preservatives and other substances that are often found in processed foods.

Celiac disease is an autoimmune disease where the body cannot properly digest and process gluten, causing damage to the small intestines. Therefore it interferes with the absorption of nutrients from food and can lead to poor nutritional status and a lowered immune status. 

Gluten intolerance/sensitivity is a condition where individuals are more sensitive to gluten, resulting in the irritation of the digestive tract. A person with an intolerance will still experience mild digestive problems after eating gluten; however, their condition is not a severe as someone who has true celiac disease.

A suspected food allergy such as gluten should always be evaluated, diagnosed, and treated by a qualified medical professional. Your physician may refer you to a specialist such as a board-certified allergist. It is important to not diagnose a food allergy on your own. Self-diagnosis can lead to unnecessary dietary restrictions and inadequate nutrition. Additionally, some people think they are allergic/intolerant to gluten when they actually have another type of food or environmental disorder, and the treatment plan may differ.

Diagnosing and Treating Gluten Allergies

The first step an allergist will take to diagnose a gluten allergy is take a thorough medical history and then perform one of the following tests:

  • Blood test for gluten antibodies
  • Oral food challenge or an elimination diet
  • A small bowel biopsy to assess gut damage

The allergist will combine your test results with the information given in your medical history to provide a diagnosis.

Allergies and sensitivities CANNOT be diagnosed from the history alone without testing or from unsupported tests such as hair samples, iridology, cytotoxic testing, pulse testing and others. These allergy tests are unregulated and potentially lead to incorrect diagnosis and treatment and may damage health.

A gluten-free diet is the only recognized method of treatment for gluten allergy and intolerances. Gluten is a protein found in wheat, rye, barley, triticale, oats and derivatives of these products (i.e. malt). A gluten-free diet avoids all foods that contain gluten. As a consequence a gluten-free diet can potentially reduce an athlete’s carbohydrate intake (an athlete’s fuel source).

Gluten-free foods that are rich in carbohydrates include: sweet potato, potato, corn, pumpkin, rice, quinoa, fruit – fresh, dried, juice and gluten-free pasta, cereal, pretzels, and bread. If you have medically diagnosed gluten or any other food allergy or sensitivity, you should consult with a registered sports dietitian for guidance on a healthy gluten-free athletic diet.

Health - Food and Facts

Carbohydrate vs. Protein

Another food myth is that carbohydrates are bad and a high protein diet is good. Names for such diets include Atkins or Paleolithic (also known as the Paleo) diet. The Paleolithic diet is based on the types of foods presumed to have been eaten by our ancestors, consisting mainly of meat, fish, vegetables, and fruit; it excludes dairy, grain products and processed food. The benefit of this diet is that individuals eat foods: lower in fat, calories, and sodium; less processed; and higher in fiber. An athlete who eats a high-protein diet because they believe a low carbohydrate diet will enhance performance is misinformed.

High protein diets can lead to:

  • Carbohydrate restriction and therefore an inability to fuel and recover from training sessions.
  • Increased risk of a compromised immune system and chance of getting sick.
  • Poor concentration, focus and decision- making during practice and matches.
  • Increased risk of suffering from early fatigue and injury.

Eating whole, unprocessed foods is desirable, however, athletes are reminded to ensure they obtain appropriate amount of energy and essential nutrients to sustain good on-court performance and off-court health. The registered sports dietitians can assist you to create a sustainable, healthy diet which meets all your nutrition needs.


There is no legal or medical definition for superfoods. This is a word used in popular culture to describe those foods which naturally have large doses of antioxidants, polyphenols, vitamins, and minerals. It has been proposed that eating them may reduce the risk of chronic disease, and prolong life. Superfoods can also be used as a marketing term to describe foods with these supposed health benefits. There are no superfoods for tennis players; rather, eating a diet based on foods from all 5 Major Food Groups plays a major role in optimizing the athlete’s health and performance.

There are sport products that have been designed for athletes to help delay the onset of fatigue, ensure hydration and aid recovery.

  • Sport drink and semi-fluid concentrated carbohydrate products such as sport gels, beans, blocks, blasts, chews and chomps. These products provide the necessary carbohydrates to ensure the players are fueled correctly.
  • Sport drinks, and electrolyte drinks. These products provide liquid and electrolytes with some sugar that enhances the uptake of fluid into the body’s cells delaying the onset of dehydration.
  • Recovery drinks, and sport bars assist with recovery. These products provide approximately 240 calories, 30+grams of carbohydrates, 15-25g protein and are low fat (< 7g fat). This is an ideal recovery food to take in immediately upon completion of a tennis practice or match. This helps replace glycogen stores, and aids muscle repair and immunity support.

On average tennis player’s hydration requirement:

  • 30grams of carbohydrates per hour of play.
  • 1.2 L/per hour of on-court play.

Any dietary regime that restricts food groups can:

  • Cause nutritional deficiencies in athletes.
  • Be dangerous.
  • Cause complications with training and competing.

For tennis players, food should be seen as fuel and eaten with the goal of optimizing performance and health.

The contents of the Health site are for informational purposes only and should not be treated as medical, psychiatric, psychological, health care or health management advice. The materials herein are not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this site. Reliance on any information provided herein is solely at your own risk.