Do Protein Shakes Make You Fat?
Written by Carina Fabia
Last updated on: Sep 27, 2022
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Protein shakes come in a variety of flavors and can be a great way to get additional protein into your diet. However, some people are concerned that drinking protein shakes may make you fat. The question is rather well-founded, though, because countless studies have shown that an excess protein diet can cause weight gain.
Excess calories from any source, including protein, will be stored as fat if you consume more than you burn. However, at the same time, there are several weight loss strategies that involve a protein-rich or protein-only diet. Perhaps the best known of these diet is the Ketogenic diet, normally referred to as the "Keto Diet" (1). So, how can you tell if a protein shake will help you lose weight or make you fat? Let's take a look at the evidence.
What Are Protein Shakes?
A protein shake is a drink made by mixing water or milk with a powder that contains protein. Protein shakes usually have other ingredients as well, such as carbohydrates, fats, vitamins, and minerals.
Protein shakes are often consumed by people who want to increase their muscle mass or lose weight. They are also sometimes used as a meal replacement or as a snack.
Do Protein Shakes Make You Fat?
There is no simple answer to this question. It depends on a variety of factors, including the type of protein powder you use, how many calories you consume from protein shakes, and how active you are.
If you consume more calories than you burn, you will gain weight regardless of where those calories come from. However, if you use a protein powder that is high in calories and consume it in addition to your regular diet, you are more likely to gain weight.
On the other hand, if you use a protein powder that is low in calories and consume it as part of a weight loss plan or as a meal replacement, you are more likely to lose weight.
Studies have shown that protein shakes can help you lose weight or gain muscle mass when used in conjunction with a healthy diet and exercise program (2, 3, 4). However, there is no evidence that protein shakes alone will cause you to lose or gain weight.
How Protein Shakes Can Lead to Weight Loss
Protein shakes can help you lose weight if you use them as part of a calorie-restricted diet. When you consume fewer calories than you burn, your body will begin to break down stored fat for energy.
Including protein shakes in your diet can help you meet your daily protein requirements and preserve muscle mass while you are in a calorie deficit. Additionally, protein has been shown to reduce hunger and promote feelings of fullness, which may help you stick to your diet (5, 6).
There is some medical evidence to suggest that protein shakes may help you lose weight. A study by Harvard students found that obese individuals who consumed a protein shake before breakfast and lunch felt full for longer and ate fewer calories at their next meal (7).
A trial showed that people who replaced one or two meals per day with a high-protein shake lost more weight than those who did not consume shakes (8). The review also found that replacing one or two meals per day with a protein shake may lead to 1–2 kg of weight loss over 12 weeks.
Protein Shakes May Help You Gain Muscle Mass
Protein shakes can also help you gain muscle mass when used in conjunction with resistance training. Several studies have shown that protein shakes can increase muscle mass and strength when combined with weightlifting (9).
Protein Shakes Are Safe for Most People
Protein shakes are safe for most people, but there are a few groups who should avoid them. People with liver or kidney disease should speak to their doctor before consuming protein supplements.
Pregnant women and young children should also avoid protein shakes unless recommended by a healthcare provider. Additionally, people who have food allergies or sensitivities should be careful when choosing a protein powder, as some contain allergens like soy, dairy, or nuts.
How Protein Shakes Can Lead to Weight Gain
Protein shakes can also lead to weight gain if they are used in excess or if they contain high-calorie ingredients. If you consume more calories than you burn, you will gain weight regardless of where those calories come from.
Additionally, some protein powders are high in calories and may contain added sugars, which can contribute to weight gain. For example, a scoop of whey protein powder generally contains 130–160 calories, while a scoop of casein protein powder contains 170 calories.
If you use a high-calorie protein powder and consume it in addition to your regular diet, you are more likely to gain weight. Additionally, if you do not exercise regularly or follow a healthy diet, you are also more likely to gain weight when using protein shakes.
Medical Evidence of Excess Protein & Weight Gain
There is some medical evidence to suggest that consuming excess protein may lead to weight gain. One study showed that people who consumed 40% of their calories from protein gained more muscle mass and fat mass than those who consumed only 15% of their calories from protein (10, 11).
Protein Shakes May Contain Allergens
Some people may be allergic to the ingredients in protein powders, such as soy, dairy, or nuts. If you have a food allergy or sensitivity, be sure to read the ingredient list carefully before purchasing or consuming a protein powder.
If you experience any symptoms after consuming a protein shake, such as hives, difficulty breathing, or swelling of the face, tongue, or throat, seek medical attention immediately.
Protein Shakes Are Not Necessary
Protein shakes are not necessary for most people unless you have difficulty getting enough protein from your diet. If you eat a variety of protein-rich foods and exercise regularly, you do not need to consume protein shakes.
Additionally, if you are trying to lose weight, you may be better off replacing one or two meals per day with a healthy, balanced meal or snack instead of relying on protein shakes.
Protein Shakes Can Be Part of a Healthy Diet
Protein shakes can be part of a healthy diet if they are used in moderation and contain high-quality ingredients. If you are trying to lose weight, you may want to replace one or two meals per day with a protein shake.
Additionally, if you are resistance training, using a protein shake in conjunction with your workout may help you build muscle mass. However, it is important to choose a protein powder that contains high-quality ingredients and to consume it in moderation. If you have any food allergies or sensitivities, be sure to choose a protein powder that does not contain allergens.
Protein shakes are not necessary for most people, but they can be part of a healthy diet if used in moderation. If you have any food allergies or sensitivities, be sure to choose a protein powder that does not contain allergens. Additionally, if you are trying to lose weight, you may want to replace one or two meals per day with a protein shake.
Key Takeaways: Can Protein Shakes Make You Fat?
Protein shakes can lead to weight gain if they are consumed in excess or if they contain high-calorie ingredients. Additionally, some protein powders are high in calories and may contain added sugars, which can contribute to weight gain.