Hello Runner,
Welcome back to your weekly moment of endurance nutrition!
Happy Weekend!
How was your week?
My week was good and a bit calmer on the work front.
I started a new course in sports nutrition for endurance athletes, and I’m loving it. It’s a very detailed course with a strong focus on clinical practice, which is great and hard to find in the world of health-related courses.
Otherwise, I stuck to my training as planned, but this week brought back the struggle of training in the heat. Temperatures have started to rise here in Spain, and the perceived exertion is already sky-high, even on a simple, light 5K run.
I suffer terribly when running in the heat, but I’ll try to stick to my training as much as I can.
For those who are new or relatively new to this newsletter, I’ve already written recommendations on what to do to make training easier in the heat.
If you haven’t read it yet, click here.
Today, I want to talk about and raise awareness regarding the expiration dates of sports nutrition products. I’ve never heard ANYONE talk about this, and unfortunately, it’s quite common to see athletes and amateurs consuming expired products. Can these expired products be harmful? Can you still use them even after they’ve expired?
A while back, a friend gave me some SIS energy gels, but he quickly warned me: “Don't wait too long to use them because they're about to expire.”
And, well, at the time, I wasn't running long enough distances to use the gels. So for quite a while, those gels sat in my pantry.
When I went to use them, I remembered what he had told me and checked the expiration date. They had expired a month ago. Even so, I decided to take them with me and use the gels.
Luckily, the texture and flavor were still the same. And I believe the effectiveness was too.
But that got me thinking: is it safe to take these products after they’ve expired? Or to what point is it safe to consume them?
Also, I thought about how many brands produce amazing, more natural products for runners who suffer from GI issues. And with these natural products, does anything change when they expire compared to products that don’t contain such natural ingredients?
Since I had a lot of questions and few answers, I sought clarification.
Let’s figure out how this works.
What Expiration Dates Actually Mean
One of the biggest misunderstandings surrounding sports nutrition products is the assumption that all expiration dates indicate immediate danger after a certain day. In reality, food labeling is more nuanced than that.
Most of these products use the phrase “Best Before” rather than “Expiration Date.” A best-before date generally refers to the period during which the manufacturer guarantees ideal quality, flavor, texture, nutrient stability, and performance. The product may still be edible afterward, but it may no longer function exactly as intended.
An actual expiration date is more serious. This type of labeling may indicate declining safety, weakening preservatives, ingredient instability, or an increased risk of spoilage.
Why Sports Nutrition Products Change Over Time
Sports nutrition products are carefully formulated systems. Manufacturers design them to survive transportation, storage, fluctuating temperatures, and the physiological demands of endurance exercise. However, no processed food remains perfectly stable forever.
As products age, several important changes begin to occur simultaneously:
Nutrients gradually degrade over time
Vitamins become less potent
Caffeine concentrations may decline
Flavor compounds break down
Certain amino acids become less stable.
This means an expired product may no longer deliver the ergogenic or nutritional effects that runners expect.
Fat oxidation is another major issue, particularly in products (energy bars, protein bars, energy balls, etc) containing nuts, oils, chocolate, or dairy ingredients. Over time, fats become rancid and produce unpleasant flavors and odors.
Texture also changes significantly with age:
Gels may crystallize or separate
Chews often become hard, sticky, or rubbery
Bars can turn stale, oily, crumbly, or excessively dry.
Finally, microbial safety becomes increasingly important over time. Although many sports nutrition products are shelf-stable due to preservatives, low water activity, and sealed packaging, the risk of contamination rises when products are exposed to heat, moisture, damaged packaging, or repeated temperature fluctuations.
What are the Main Health Risks?
The most common issue associated with expired sports nutrition products is gastrointestinal distress.
Symptoms can include:
Bloating, nausea, reflux, cramping, vomiting, and diarrhea.
During running, these problems can rapidly lead to dehydration, sodium imbalance, inability to continue fueling, and severe performance decline.
Foodborne illness is less common but more serious. The risk becomes higher when products contain dairy ingredients, have damaged packaging, or have been exposed to moisture and heat. Severe vomiting, fever, abdominal pain, and diarrhea are possible signs of contamination.
Expired products may also simply fail to work as intended. Carbohydrate delivery may become less reliable, caffeine potency may decline, and electrolyte replacement may become inconsistent. Even if safety is not compromised, performance may still suffer.
RECOMMENDATION
What should you do with each type of product?
→ Energy Gels
Among sports nutrition products, gels are generally considered relatively low-risk from a microbial perspective because they usually contain concentrated sugars, acidic ingredients, and preservatives that inhibit bacterial growth.
While consuming a slightly expired gel is unlikely to cause severe harm if the packaging remains intact, runners should still inspect the product carefully. Any swollen packaging, leaking, fermentation-like odor, discoloration, or visible mold should be treated as a clear sign to discard the product immediately.
→ Energy Chews
Energy chews are somewhat more vulnerable than gels because they often contain gelatin, pectin, fruit concentrates, and higher moisture levels.
Over time, chews may harden significantly or melt and resolidify if exposed to heat.
If chews show unusual stickiness, hardening, discoloration, or signs of mold, they should not be consumed.
→ Sports Drink Powders
Dry sports drink powders are relatively stable when stored correctly in cool, dry conditions. However, moisture exposure changes the situation considerably.
Humidity can cause powders to clump and may accelerate nutrient degradation or microbial contamination. Vitamins are especially sensitive to heat and humidity, meaning older powders may provide less nutritional value even if they remain technically safe.
Most expired powders primarily suffer from reduced quality and flavor rather than severe safety risks, but products exposed to moisture or damaged packaging should be discarded.
→ Ready-to-drink Sports Drinks
Ready-to-drink products are more vulnerable because they contain water, which creates a better environment for microbial growth.
As these beverages age, preservatives gradually become less effective. Flavor changes, unusual carbonation, swelling bottles, or damaged seals should all be considered warning signs.
Runners should never consume ready-to-drink sports beverages that appear swollen, smell unusual, or show any indication of compromised packaging integrity.
→ Protein Bars and Energy Bars
Protein bars are among the most problematic ones because they often contain fats, dairy proteins, nuts, oils, and moisture-containing ingredients.
These components are vulnerable to oxidation and spoilage. As bars age, they frequently become rancid, excessively dry, oily, or unpleasant in taste and texture.
Heat exposure accelerates this process dramatically. A protein bar left in a hot car for several weeks may deteriorate more severely than one stored correctly for several months past its best-before date.
Consuming degraded bars may lead to nausea, stomach discomfort, vomiting, diarrhea, or significant gastrointestinal distress during exercise.
→ Products made with natural ingredients and free of preservatives
Because they are made with natural ingredients such as fruits, olive oils, juices, etc., these types of products should be discarded immediately after their expiration date.
The safest strategy is to avoid using expired products during races, long runs, or key workouts.
Products that are only slightly beyond their best-before date and have been stored properly may sometimes still be acceptable for low-risk training sessions, particularly if they are simple carbohydrate-based products such as gels or dry drink mixes. However, runners should always inspect packaging carefully before use.
Runners can reduce waste by rotating stock regularly, avoiding excessive bulk purchases, and storing products in cool, dry, temperature-stable environments.
Product of the Week
This week's Product of the Week is the Salssa Perform.
Salssa is a Spanish brand, from Barcelona, that really caught my attention when I discovered it.
They make sports nutrition products for runners using only natural ingredients, most of which come from the Mediterranean.
Perform is a gel with 31 g of carbs to use before and during workouts. The best part is that the package comes with a lid, so you can take it little by little.
It’s worth giving it a try.
Track of the Week 🎧️
This week's Track of the Week is a remix of an older song that I love. This remix is perfect for listening to while training.
I’ve chosen We Are Young - Alvin Risk Remix by Fun, Janelle Monáe, and Alvin Risk
Any questions or something you would like to share, drop me an email
Wishing you a great weekend and week ahead!
Here’s to health and good runs⚡️
Ana Paula Alonso