Can You Use Whey Protein As A Meal Replacement? (Answer: No)

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Protein shakes are very convenient and require little prep, so many of my nutrition clients wonder if they can have a protein shake to replace a meal when they’re on the go.

Can whey protein be a meal replacement? No, whey protein powder is not a meal replacement because it lacks sufficient carbs, fats, and micronutrients to be considered a meal. A whey protein shake could replace your protein source in a meal, but it should still be paired with a source of carbs, fat, and ideally a fruit or vegetable.

It’s important to understand how you can upgrade your protein powder to make it a meal replacement because it’s often easier to consume a meal replacement instead of a meal when you’re on the go.

Key Takeaways

• Whey protein by itself shouldn’t be used as a meal replacement.

• Using whey protein as a meal replacement could negatively impact your body weight and cause nutrient deficiencies.

• There are some protein powders that are considered meal replacements that contain other ingredients than just whey protein.

What Defines a “Meal” & “Meal Replacement”?

A meal is a collection of foods that provide sufficient energy to support your daily activities and the nutrients your body needs to function optimally.

A meal replacement is a more convenient meal option (typically in liquid form and in smaller serving sizes) that provides you with the same calories and nutrients as a traditional meal.

Although quality meal replacements will provide everything you need energetically, you should still choose whole foods whenever you can because they contain more nutrients (fiber, vitamins, minerals) that your body needs to function optimally.

According to registered dietitian Christina Fasulo:

“Meal replacement shakes are pre-made shakes that are typically between 150-400 calories, with a combination of carbohydrates, fats, and protein. These shakes can serve as a convenient substitute to cooking a balanced meal or snack…Even though they can be a convenient way to get a somewhat nourishing meal, they will never completely replace a healthy diet based on whole foods.”

Christina Fasulo

4 Reasons Why Whey Protein Can’t Be a Meal Replacement

Whey protein by itself cannot be a meal because:

• Its calorie content is too low

• It lacks a sufficient amount of carbohydrates

• It doesn’t provide an adequate amount of fat

• It lacks micronutrients

Its Calorie Content Is Too Low

Protein powder generally has between 100 to 140 calories, which isn’t enough to provide you with the energy needed for basic daily activities. A meal should have a minimum of 200 calories to keep you properly fueled.

If you’re not getting enough calories at a meal, you will feel much more fatigued throughout the day, which could impact your physical and mental performance.

For example, if you only have a protein shake at lunch and don’t eat again until supper, you’ll feel tired all afternoon and probably be ravenous by the time supper rolls around.

It Lacks a Sufficient Amount of Carbohydrates

One of the main nutrients that whey protein powder lacks to make it an appropriate meal replacement is carbohydrates, which are your body’s preferred source of energy. 

Additionally, high-quality carbs contain fiber, which plays a key role in digestion. Without sufficient fiber in your diet, your risk of digestive issues (i.e., constipation, irritable bowel syndrome, and diverticulitis) increases.

As a nutrition coach, I recommend aiming for at least 20 grams of carbs in each meal to ensure you have enough energy to get through the day.

• Related Article: Does Protein Powder Have Carbs? 8 Types of Protein Explained

It Doesn’t Provide an Adequate Amount of Fat

The other major nutrient that whey protein powder lacks is a quality fat source. Having a fat source in your meal is important to ensure you’re consuming enough daily fat to support your hormonal health and manage inflammation.

A meal replacement should have at least 10 grams of fat to ensure adequate fat intake. Ideally, this fat source would have more unsaturated fat than saturated fat to promote heart health.

• Related Article: Meal Replacement vs Mass Gainer: Differences, Pros, Cons

It Lacks Micronutrients

Whey protein powder also lacks micronutrients (vitamins and minerals), which your body needs to function optimally. A quality meal replacement should have a variety of micronutrients so you get all the nutrients your body needs in sufficient quantities.

If you’re upgrading your protein powder by pairing it with whole foods, you can easily add a variety of nutrients by including different foods with different nutrient profiles. I provide some examples below of ways to make protein powder a more complete meal full of nutrients.

If you’re purchasing a meal replacement product, it’s important to look for one with whole food ingredients because these products are more likely to provide you with quality nutrients.

• Related Article: Does Whey Protein Have Calcium? (A Nutrition Coach Answers)

Are There Risks if You Use Whey Protein To Substitute a Meal?

If you’re using whey protein as a replacement for your meal every once in a while, there is no major risk. It still isn’t ideal, but when it’s the difference between not eating at all or consuming a protein shake, you’re better off having the protein shake.

Whey protein as a meal replacement becomes a problem when you’re doing it daily, causing you to miss out on important nutrients.

When you “skip a meal” by only having whey protein, two things can happen:

1. You undereat, decreasing your energy levels and putting you at risk for nutrient deficiencies.

2. You compensate for the missed meal by overeating later in the day (generally not the “healthiest “ foods), causing you to gain excessive amounts of fat.

Either way, missing out on a proper meal too frequently doesn’t end well. It’s important to be better prepared to get the calories and nutrients you need at meal times.

• Related Article: Are Premier Protein Shakes Good

How To Make Whey Protein a Meal Replacement

Whey protein can’t be a meal replacement by itself, but you can pair it with other foods to make it a suitable meal replacement option.

As a reminder, a meal should have more than 200 calories and sufficient amounts of protein (20-40g), carbs (>20g), fat (10-20g), and some micronutrients (not required, but recommended).

Here are a few examples of how to pair your whey protein with other foods to make it a better-quality meal:

• Smoothie: 
  • 1 scoop of whey protein + 1 cup of frozen fruit + 1 cup of almond milk (or milk of choice) + 1 tbsp of peanut butter
  • 346 calories, 35 grams of protein, 30 grams of carbs, and 12 grams of fat

• Protein Shake with Apple and Cheese:
  • 1 scoop of whey protein + 1 cup of almond milk (or milk of choice) + a large apple + 30 grams of cheese
  • 391 calories, 36 grams of protein, 31 grams of carbs, 16 grams of fat

• Protein Oatmeal: 
  • 1 scoop of whey protein + ½ cup of oats + 1 cup of water + ½ cup of berries + 1 tbsp nut butter
  • 375 calories, 36 grams of protein, 36 grams of carbs, 11 grams of fat

• Yogurt Bowl:
  • 1 cup of Greek yogurt + ½ scoop of whey protein + ½ cup of granola + ½ cup of berries
  • 425 calories, 39 grams of protein, 47 grams of carbs, 11 grams of fat 

• Protein Shake and Muffin:
  • 1 scoop of whey protein + 1 cup of almond milk (or milk of choice) + a medium-sized blueberry muffin
  • 474 calories, 35 grams of protein, 57 grams of carbs, 12 grams of fat

Which Protein Is the Best Meal Replacement? 

If it’s easier for you to consume a liquid meal replacement because of time constraints, an inability to chew solid foods, or the nature of your job, the best meal replacement you could get is Bare Performance Nutrition’s Strong Food Complete Meal Replacement.

The Strong Food Meal Replacement is made with real food ingredients, including: “Gluten-Free Oat Powder, Sweet Potato Powder, Whey Protein Isolate, Pea Protein, MCT Powder, Macadamia Nut Oil Powder, Flaxseed, Chia Protein, Pink Himalayan Salt.”

Per serving (3 scoops), you get 490 calories, 40 grams of protein, 48 grams of carbs, and 15 grams of fat.

For those who are gluten and/or dairy free, the Soylent Complete Nutrition Meal Replacement is a better option. It contains plant-based protein, essential vitamins and minerals, omega 3 & 6 fatty acids, and BCAAs (branched-chain amino acids).

For a 12 fluid oz serving (the amount of powder to mix with 12 fl oz of liquid), you get 400 calories, 20 grams of protein, 41 grams of carbs, and 20 grams of fat.

Frequently Asked Questions

Do Meal Replacements Have Protein?

Meal replacements do have protein because a meal is not complete without a sufficient amount of protein. Most quality meal replacements will have a similar amount of protein as a standard protein powder (20-40 grams).

Will Replacing a Meal With Whey Protein Help Me Lose Weight?

Replacing a meal with protein could lead to weight loss if it causes you to eat fewer calories than you need to maintain your weight. However, skipping a quality meal is not the best method for weight loss because it’s not sustainable, so you likely won’t keep this weight off long-term.

What To Read Next

• Drinking Whey Protein On An Empty Stomach (3 Things To Know)
• How Long Does Whey Protein Take To Digest + Why It Matters
• Drinking Whey Protein Every Day (Are There Drawbacks?)
• Can You Cook With Protein Powder? (Yes, Here’s How)
• Can You Take Whey Protein Without Working Out? (Science-Backed)
• Protein Shake Fast: What Is It + 6 Reasons NOT To Do One

References

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Fritsche K. L. (2015). The science of fatty acids and inflammation. Advances in nutrition (Bethesda, Md.), 6(3), 293S–301S. https://doi.org/10.3945/an.114.006940

M F Oliver, It is more important to increase the intake of unsaturated fats than to decrease the intake of saturated fats: evidence from clinical trials relating to ischemic heart disease, The American Journal of Clinical Nutrition, Volume 66, Issue 4, October 1997, Pages 980S–986S, https://doi.org/10.1093/ajcn/66.4.980S

Shenkin A. (2006). Micronutrients in health and disease. Postgraduate medical journal, 82(971), 559–567. https://doi.org/10.1136/pgmj.2006.047670