When Should I Eat A Protein Bar? Protein bars are a great way to have a nutrient dense, high protein meal or snack when on the go. With over 1,300 different protein bars available, it is sometimes hard to choose which bars are best for you. This complete Protein bar guide will walk you through everything you need to know when choosing your next protein bar.
Are Protein Bars Good for You?
Protein bars are a popular snack food designed to be a convenient source of nutrition.
Many people enjoy them because they’re a quick way to add protein and other nutrients to a busy and active lifestyle.
Given the wide variety of protein bars on the market, it’s important to know that not all protein bars are created equal.
This article reviews whether protein bars are healthy, what benefits they may offer, and the best ways to incorporate them into your lifestyle.

Protein bar nutrition
The nutrient composition of protein bars can differ significantly between brands — and even between flavors.
This is largely due to their varying ingredients. Many protein bars may be made from dates and dried fruit, nuts and seeds, and whole grains like oats or quinoa.
The average protein bar contains 5–10 grams of fat, 25–35 grams of carbs, and 5–10 grams of fiber.
In addition to offering protein and carbs, many protein bars are a good source of micronutrients, such as calcium, B vitamins, potassium, and iron.
When examining ingredient labels, be aware that some protein bars use a proprietary blend of ingredients and don’t disclose any of its details on the packaging
Many protein bars also contain high amounts of added sugar and use unhealthy sweeteners like high fructose corn syrup, which adds excess fructose to your diet and can increase your risk of fatty liver, obesity, and diabetes when consumed in high amounts.
Generally, most protein bars offer 150–400 calories and 10–20 grams of protein, although some contain closer to 30 grams of protein per serving.
The source of protein also varies. Some bars feature yogurt powder, milk, or dairy proteins like casein and whey, while others use plant-based sources like soy, pea, or brown rice. Some contain egg whites, while others rely on nuts and seeds as a primary protein source.
Moreover, some protein bars use highly concentrated protein sources like whey or soy protein isolates, instead of less processed, whole food protein options.
SUMMARY
The nutritional profiles of protein bars can vary substantially between brands and flavors, depending on the ingredients used. This influences the calorie, protein, fat, and fiber contents, as well as which vitamins and minerals a protein bar offers.
The Protein Window: When’s the Best Time to Eat Protein Bars?
When is the best time to eat a protein bar?
Well – that depends on several factors: from who you ask to what your goals are.
If your goal is to use protein bars as a healthier alternative to common snacks, you can eat them whenever you want. However, if you’re aiming to build muscle and maximise your ‘gains’, it’s worth being aware of a time window that bodybuilders call the ‘protein window’.
However, before you start timing all of your protein intakes for that specific, narrow time in your day, remember that the protein window is not actually a proven fact and is, at best, a sensible theory that leverages essential bodily functions.
What is the protein window?
When you do strength training activities, your body’s muscle fibres are damaged and then slowly repaired. The fusion of damaged fibres strengthens and increases their mass and size – which results in muscle growth. Most studies agree that consuming 1.6-2g of protein per kilogram (kg) of body weight daily will aid in this process.
That process is known as ‘anabolic’ – a term to describe your body’s molecules being formed into bigger, more complex molecules. It’s the opposite of catabolic, where molecules become smaller.
Theories suggest that this anabolic process occurs most readily in the 30 minutes following a workout. The same theories also suggest that during the anabolic window, the body’s ability to synthesise protein is at its best – but the breakdown of protein is also at its max.
The theories around protein bar timing stem from the idea that maximising protein intake in the first 30 minutes post-workout will A) decrease muscle protein breakdown and B) increase muscle protein synthesis.
However, the science is out on this theory. Many studies, including this meta-analysis, have shown that while there is an increase in protein synthesis following a workout, it’s not necessary to eat protein in that window to prevent muscle breakdown. The research states that: “these results would seem to refute the commonly held belief that the timing of protein intake in the immediate pre and post-workout period is critical to muscular adaptations”.
The only proven occasion that this is true is if you’ve worked out in a fasted state – where studies have shown that fasting significantly increases post-workout muscle breakdown.
When to eat protein bars
The science discussed above essentially supports the idea that while protein intake is important for muscle growth – timing is far less relevant.
With that in mind, timing your protein bar intake is relatively simple. Pre-workout protein bars are a good idea for those who know they will be hitting the gym in a few hours but want a snack that won’t be overly indulgent. Protein increases feelings of satiety, so it can help stave off hunger cravings until you’ve done your workout and can eat a full meal to refuel.
Pre-workout protein bars are also beneficial thanks to their carbohydrate content – especially those that use good sources of carbohydrates, such as our bars made using oats. These carbohydrates will help fuel your workout while your body will use the protein to synthesise protein and rebuild muscle fibre.
Post-workout protein bars are also a good idea – they’ll help itch that ‘snack’ craving or stave off hunger and get calories back into your body post-workout when you aren’t enjoying a meal for a few more hours.
When is the best time to eat a protein bar?
Honestly, this answer seems to entirely depend on you and your own body. There is no real ‘best’ time – protein bars are perfect as both pre-workout and post-workout snacks, although those looking to optimise nutrition fully will want to choose the more carbohydrate-heavy protein bars for pre-workout and options with fewer carbs for post-workout.
The ‘best’ time depends on you: some people can’t manage a full breakfast in the morning – in which case protein bars are a great replacement to ensure you still reach your protein intake goals. If you’re time-precious, protein bars make for good and accessible replacements.
While studies are not conclusive, pre-workout protein bars will likely assist with energy in the gym. In contrast, post-workout protein bars help increase protein availability to boost protein synthesis.
Looking for the Best Protein Bars?

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There’s no question that protein is an essential part of a healthy diet: Research suggests that protein keeps you feeling full, helps muscle recovery after a workout, can contribute to weight loss, and may even lower blood pressure. A recent study published in Circulation, the journal of the American Heart Association, found that replacing the calories in refined carbs with a daily 40-gram (g) supplement of milk or soy protein lowered blood pressure modestly. All these benefits help explain why protein bars have become a diet staple in the United States.
Protein bars are a type of nutritional supplement that comes in a variety of brands and flavors — chocolate, dark chocolate, almond, vanilla, peanut butter and chocolate, oatmeal, and more. Many protein bars have a good balance of carbohydrates, protein, and fat, making them a nice choice for a snack or postworkout recovery boost. Some protein bars are higher in sugar while others use sugar alcohols.
The only problem, says Jessica Janc, a certified sports nutritionist with the National Association of Sports Nutrition, is that not all protein bars are created equal — many protein bar brands are so loaded with sugar, they’re more like delicious candy bars than dietary supplements. The key, Janc says, is selecting a protein bar with the right building blocks — protein should be at least half the amount of the bar’s carbohydrates. “For instance, if the bar has 24 grams of carbohydrates, I would want it to have at least 12 grams of protein,” Janc explains. “I like the sugars to be below 7 grams and the fat to be below 12 grams.”
Similarly, Ericka Stachura, RD, of Boston, recommends dieters watch the sugar, protein, and fiber in protein bars. “For a snack, look for protein bars with 200 calories or less,” she says. “For an on-the-go meal replacement, look for bars that have 200 calories or more. Serious athletes who want a postworkout recovery protein bar should look for bars with about 20 grams of protein. It’s also a good idea to look for a short ingredients list to ensure your bar is minimally processed.”
But what if you indulge in several pure protein bars each day, could you be getting too much protein? According to the Mayo Clinic, most Americans get twice as much protein as they need. Even without protein bars and other dietary supplements, athletes are getting more protein than is needed. This happens because calorie requirements are higher for athletes, who burn lots of calories, and eating more food increases the intake of protein. In addition, it’s not uncommon for athletes to intentionally seek out higher levels of protein because they think it will help them build more muscle.
For the average person, the least amount of protein you need each day in order to stay healthy is 0.8 g per kilogram (kg) (or 0.36 g per pound). With a typical diet, that amount is easy to get without even thinking about it. People who exercise regularly need a little more, at about 1.1 to 1.5 g of protein per kg of body weight while those who lift weights or are training for a marathon or cycling event need 1.2 to 1.7 g per kg. Excessive protein intake is considered about 2.5 g per kg of body weight daily.
For women ages 40 to 50, protein needs increase to about 1 to 1.2 g per kg of body weight. This is because women at midlife begin to lose muscle mass (sarcopenia) with aging. Experts believe added protein may help prevent this health condition. For those who already have sarcopenia, 1.2 to 1.5 g per kg per day may be needed.
Read on to find out about the best protein bars for every diet.
Quest Bar May Be the Best Protein Bar for Athletes

Calories: 200
Protein: 20 g
Total carbs: 22 g
Total fat: 9 g (0.5 saturated)
Sugar: 2 g
If you want a protein bar that’s great for athletes, Janc suggests Quest bars for their low-sugar and low-fat levels and focus on whole, natural ingredients. “Quest bars are all natural, low in sugar, and have 20 grams of protein,” Janc explains. “Plus, they taste good!”
Pure Protein Bars Are Highly Nutritious and Taste Great

Calories: 190
Protein: 20 g
Total carbs: 17 g
Total fat: 6 g (3 saturated)
Sugar: 2 g
When it comes to overall nutrition, Janc likes Pure Protein bars because of their high protein-to-carbohydrate ratio. And, she says, these bars don’t have that chalky protein-supplement taste.
Check Out Power Crunch Bars for a Crunchy, Sweet Snack

Calories: 205
Protein: 14 g
Total carbs: 10 g
Total fat: 12 g (4 saturated)
Sugar: 5 g
If you’re in the mood for a crunchy, sweet snack that’s different in texture from traditional protein bars, Power Crunch bars will leave you satisfied and provide a solid dose of nutrition, Janc says. “It tastes like a cookie, and it has 14 grams of protein, 10 grams of carbs, and only 5 grams of sugar,” she adds.
Detour Bars Are a Low-Calorie Protein Bar

Calories: 150
Protein: 15 g
Total carbs: 34 g
Total fat: 9 g (6 saturated)
Sugar: 5 g
Opt for the smaller-sized Detour bar for a low-calorie snack option that still packs 15 g of protein. “Detour bars taste great and have only 150 calories and 5 grams of sugar plus 15 grams of protein and 34 grams of carbohydrates,” Janc says.
Choose Met-Rx Bars for a Meal Replacement

Calories: 310
Protein: 30 g
Total carbs: 33 g
Total fat: 10 g (6 saturated)
Sugar: 3 g
To be used as a meal replacement, this protein bar packs a big-time protein punch with very little added sugar or carbohydrates. For a healthy snack, Janc suggests opting for the smaller-sized Met-Rx bar. “The Met-Rx small bar has 200 calories, 19 grams of protein to 24 grams of carbohydrates, and only 5 grams of sugar,” she says.
Think Thin Bars Are Gluten- and Sugar-Free

Calories: 230
Protein: 20 g
Total carbs: 23 g
Total fat: 8 g (3.5 saturated)
Sugar: 0 g
If you’re gluten-free or keep kosher, Think Thin bars will meet your requirements, plus they are sugar-free and have only 23 g of carbs to 20 g of protein. “Although they have zero sugar, they do contain sugar alcohols, which come from carbs in fruits and vegetables and can upset your stomach [if you have too much],” Janc cautions. “But the bars taste great!”
Downsides and precautions
Countless protein bar options are available today. This can make it difficult to determine which one is best for you, as well as easy to choose one that may not be a good fit for your goals.
Some protein bars are so high in calories and added sugar that they might as well be in the candy aisle.
To enhance the flavor, many use added sweeteners, which can vary from more natural sweeteners like dates or stevia to unhealthy ones like high fructose corn syrup. Many protein bars use cane sugar or honey, which may not align with your personal preferences.
Additionally, while the fat in some protein bars often comes from whole nuts and seeds, others use highly processed plant oils, like palm, canola, peanut, or soybean oil.
If you’re eating protein bars solely for their protein, keep in mind that most people consume more protein than they need, so you may already be getting enough of this nutrient.
Eating protein in excess doesn’t appear to benefit the health of the average person, and doing so may be harmful in some cases.
One review of 32 human studies found that eating more protein than the recommend dietary allowance (RDA) of 0.36 grams per pound (0.8 grams per kg) of body weight was associated with an increased risk of cancer, heart disease, and bone, liver, and kidney disorders.
However, other studies report that high daily protein intake of around 1.4 grams per pound (3 grams per kg) of body weight is safe, at least in the short term.
For example, a study in 14 resistance-trained men showed that a daily protein intake of over 1.5 grams per pound (3.3 grams per kg) of body weight for 6 months was not associated with any adverse health effects. Other studies have shown similar results
Although more research on the long-term health effects of high protein diets is needed, it’s likely that for most people, consuming the recommended 0.36 grams of protien per pound (0.8 grams per kg) of body weight daily is sufficient.
Nevertheless, keep in mind that some people, including athletes, pregnant and breastfeeding women, and those with certain chronic illnesses, need more protein on a daily basis than the general population.
Lastly, protein bars can vary greatly in their cost and may not be worth their price tag. In addition to checking for high quality ingredients, it may help to compare the unit price and determine which brands offer the greatest value.
The right protein bar for you depends on your goals and values. Select those with a short ingredient list that primarily use whole foods rather than highly processed ingredients. Choosing protein bars that have minimal to no added sugars is also recommended.
SUMMARY
Protein bars not only vary in nutritional content but also ingredients. Some are high in added sugar and may be an unnecessary source of excessive protein. Examine the packaging to determine whether a protein bar meets your personal goals and needs.