Whey Protein vs Fish For Weight Loss

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Whey Protein vs Fish For Weight Loss

When it comes to shedding those extra pounds, the options seem endless. From various foods to an array of supplements, the choices can be overwhelming. However, there are a few key players that stand out for their significant impact on weight loss. Two such contenders are whey protein and fish. 

Whey protein and fish can play essential roles in a balanced diet and can be beneficial for weight loss. Whey protein is known for its high protein content and muscle recovery benefits, while fish is a lean protein source rich in omega-3 fatty acids that support satiety and heart health. Including both in your diet can provide a well-rounded approach to nutrition for weight loss goals. But which one is more effective for weight loss?

Read on to learn about whey protein vs fish for weight loss and their potential benefits, as well as their differences.

Whey Protein For Weight Loss

Whey protein is good for weight loss because it can make you feel fuller and help you lose fat. One of the main reasons it is so good for weight loss is that it is low in carbs, calories, and fats while high in protein.

Proteins such as whey are often used to help people lose weight. Protein shakes or other meals with high-quality whey protein can help the body function at its best and bring several benefits, such as a feeling of fullness that lasts longer, help with building and keeping muscle mass, and metabolism stimulation1,2,3,4.

Benefits Of Whey Protein

Whey protein is a popular dietary supplement known for its numerous benefits, particularly in fitness and muscle building. Here are some of the key benefits of whey protein:

May Encourage Weight Loss

Whey protein may help curb your hunger, which can help you lose weight. Studies show that eating whey protein makes you feel less hungry and increases hormones like peptide YY (PYY) and glucagon-like peptide 1 (GLP-1), which make you feel full5.

In 2011, a study with 90 people who were overweight or obese found that those who took 56 grams of whey protein per day for 23 weeks lost 5 pounds (2.3 kg) more fat than those who took soy protein6.

Boost Metabolism

Whey protein shakes are a cheap way to get complete protein. To understand how whey can help you lose weight, you should think about your metabolism. It is an essential part of losing weight. The metabolism process is how your body turns the food and drink you eat into energy. The more calories you burn, the faster your metabolism works. Also, it keeps the body from turning the extra power into fat.

Eating a lot of protein speeds up your metabolism and makes you burn more calories than normal. Protein can also help you build lean muscle, especially during power training. People with more muscle mass require more effort to maintain it. Studies have shown that 10 pounds of muscle burns about 50 calories daily, while 10 pounds of fat burns about 20 calories daily3,7.

Muscle Building And Maintenance

Protein helps keep muscles in good shape and build new ones. When you go on a diet with calorie loss, there is a risk that your body will break down muscles more quickly, especially if you don’t get enough branched-chain amino acids. Having enough protein can stop this from happening.

BCAAs are essential amino acids that are found in whey protein isolate. Leucine is an amino acid that can simultaneously stop muscles from breaking down and boost physical ability. With whey protein shakes, you can drop weight while keeping your muscle mass2.

Help Reduce Heart Disease Risk Factors

Your risk of getting heart disease rests on several things, like how much you weigh, how high your blood pressure is, and how much sugar is in your blood.

Studies show that eating whey protein may help lower high blood pressure, blood sugar, and cholesterol levels, all risk factors for heart disease.

In 2018, researchers looked at nine studies and found that when people took whey protein supplements, their blood pressure, glucose, heart-healthy HDL, and total cholesterol improved8.

In addition, a 2020 review of 22 studies also found that people who ate whey protein had lower hemoglobin A1c (HbA1c) levels, a long-term indicator of blood sugar control, as well as fat levels, total cholesterol, and LDL cholesterol9.

Side Effects Of Whey Protein

Most whey proteins are safe and have few side effects. However, some side effects and details may need to be considered. Such as:

Not Appropriate For Vegans

Whey protein is derived from the milk of animals like cows and goats, making it unsuitable for those who adhere to a vegan diet and avoid all animal products.

May Cause Acne In Some People

Whey protein may cause the body to make more hormones like IGF-1, which could make acne worse. A 2013 study of 30 people between the ages of 18 and 45 found that using whey protein was linked to getting acne after two months10.

May Cause Digestive Upset

People who have trouble digesting the milk sugar lactose may have stomach problems like bloating and gas after eating lactose-containing foods such as whey protein concentrate. People who can’t handle lactose should buy lactose-free protein powders like peas or whey protein supplements.

Note: Kids and people allergic to milk should not take whey protein. Milk allergies are more common in kids, but adults can also have them11.

Fish For Weight Loss

Fish has always been a favorite food for many people. It is the best catch for people who like fish. Popular ones like salmon and tuna are favored because it tastes good and is suitable for most diets. But the question that everyone wants to know is, “Is fish good for losing weight?” In the following parts of this article, we’ll discuss how fish can help you lose weight.

Fish is full of vitamins, minerals, protein supplement, and omega-3 fatty acids, making it a good choice for people trying to lose weight. In particular, as a lean protein source, it offers a distinct advantage over other options by providing minimal unhealthy fats and calories. Protein takes the spotlight in weight loss efforts, as it plays a vital role in promoting satiety, ensuring you stay full and content for extended periods. 

But that’s not the only good thing about fish. It is also a staple food in many countries worldwide, and it has many other health benefits that make it a great choice for people of all ages.

While adding lean fish to your diet helps you lose weight faster, it is important to prepare them with healthy cooking methods, like grilling or baking. Likewise, to get the most out of this healthy food, you should also pay attention to how much you eat12.

Benefits Of Fish

Fish offers several benefits aside from being a staple for weight loss diets. These can be:

High Protein Content

Fish is a great way to get high-quality protein, which helps you lose weight. Numerous studies support protein in helping you feel full. When you feel full, you eat less, which helps you lose weight. Fish is also a better way to lose weight than red meat or chicken because it has less fat and calories than those foods. Cod and salmon are two fish that are high in energy13.

High In Omega-3 Fatty Acids

Fish is rich in omega-3 fatty acids, which are beneficial fats that can aid in weight loss. Omega-3s have the ability to boost your metabolism, which is the body’s process of converting food and water into energy. During this process, calories from your meals combine with oxygen and are utilized as energy. Your metabolic rate determines the number of calories you burn each day. By consuming fish and its omega-3s, your metabolism can be accelerated, leading to an increased calorie burn. This calorie burn can contribute to weight loss by creating a calorie deficit14.

Low In Saturated Fats

Saturated fat might make you more likely to get heart disease and gain weight. Studies show that choosing fish low in saturated fat can help you stay within your daily calorie and fat limits, which can help you reach your weight loss goals. In addition, fish with low saturated fat is often high in protein and omega-3 fatty acids, which help you lose weight. Salmon, rohu, trout, and cod are all fish that are low in fatty fat15.

Anti-Inflammatory Properties

The body often goes through a process called inflammation. Chronic inflammation, on the other hand, can lead to several health problems, such as weight gain and obesity. Studies show that fish has a lot of anti-inflammatory properties that can help lower chronic inflammation. Omega-3 fatty acids, which help lower inflammation in the body, are one of these properties. So, fish can help you lose weight by making you healthier generally and lowering your risk of health problems caused by being overweight16.

Improved Brain Function

Fish is good for your body and can help your mind work better. Omega-3 fatty acids like DHA and EPA help keep the brain healthy and make thinking easier. Better brain function helps people lose weight by making them better at making decisions and more motivated to live a healthy lifestyle. Vitamins D and B12 in fish have also been linked to better brain function. So, if you eat fish, you can not only improve your physical health but also your mental health17.

Side Effects Of Fish

While fish can contribute to plenty of benefits, certain side effects can arise from fish consumption under specific circumstances or due to individual sensitivities. Here are some potential side effects:

Mercury Contamination

Certain species of fish, giant predatory fish such as sharks, swordfish, king mackerel, and tilefish, may contain high levels of mercury. Prolonged exposure to high levels of mercury can lead to neurological issues, especially in unborn babies and young children. Pregnant women, nursing mothers, and young children should limit their protein intake of these fish18.

Allergic Reactions

Some individuals may be allergic to fish or certain types of fish. Fish allergies are relatively common and can cause skin rashes, hives, itching, swelling, difficulty breathing, and digestive issues19,20. Severe allergic reactions can be life-threatening and require immediate medical attention.

Foodborne Illnesses

Fish can be a source of foodborne illnesses if contaminated with bacteria, viruses, parasites, or toxins. Improper handling, storage, or fish preparation can lead to infections such as salmonellosis or bacterial gastroenteritis21. It is essential to ensure that fish is cooked thoroughly to kill potential pathogens.

Histamine Poisoning

Some individuals may experience histamine or scombroid poisoning after consuming spoiled or improperly stored fish22. This occurs when bacteria in the fish convert histidine (an amino acid) into histamine. Symptoms may include flushing of the face, headache, sweating, dizziness, nausea, vomiting, and diarrhea. Histamine poisoning is generally not life-threatening and resolves within a few hours.

Gout Flares

People with gout, a form of arthritis, may need to limit their intake of certain fish due to their high purine content. Purines can break down into uric acid, triggering gout flares in susceptible individuals23. Fish with high purine levels include anchovies, sardines, mussels, herring, and scallops. However, not all individuals with gout are sensitive to these purine-rich foods, so that it may vary from person to person.

Key Comparison: Whey Protein vs Fish For Weight Loss

Whey Protein

  • High in protein: Whey protein powder is a concentrated source of protein, which is essential for weight loss as it helps preserve lean muscle mass and promotes satiety.
  • Convenient: Whey protein powder is easy to incorporate into your diet as a quick and convenient source of protein. It can be easily mixed into shakes, smoothies, or added to recipes.
  • Low in calories: Whey protein powder is typically low in calories, making it suitable for calorie-controlled diets.
  • Fast absorption: Whey protein is quickly absorbed by the body, making it an ideal option for post-workout recovery and muscle protein synthesis.


  • Protein and nutrients: Fish is a natural source of protein and provides essential nutrients such as omega-3 fatty acids, vitamins, and minerals that support overall health.
  • Satiety and appetite control: The protein and healthy fats in fish can help increase satiety and keep you full longer, reducing the likelihood of overeating.
  • Heart-healthy fats: Fatty fish are rich in omega-3 fatty acids and is associated with various health benefits, including weight loss and improved heart health.
  • Versatility: Fish offers various species and cooking methods, allowing diverse and flavorful meal options.

Both whey protein and fish can contribute to weight loss due to their high protein content and other beneficial properties. However, individual preferences, dietary restrictions, and overall diet composition should be considered when choosing between the two.


Whey protein and fish can both be beneficial for weight loss. Whey protein is low in carbs, calories, and fats while high in protein, making it helpful in curbing hunger, boosting metabolism, and preserving muscle mass. It can also help reduce heart disease risk factors. Fish is a lean protein source rich in omega-3 fatty acids, which promote satiety, improve metabolism, and have anti-inflammatory properties. Fish is also low in saturated fats and high in essential nutrients.

However, both contain some side effects. Whey protein is not suitable for vegans and may cause acne or digestive upset in some individuals. As for fish, in some instances, it may have potential side effects such as mercury contamination, allergic reactions, foodborne illnesses, histamine poisoning, and gout flares.

Both whey protein and fish have advantages and can be incorporated into a balanced weight-loss diet. Individual preferences and dietary needs should be considered when choosing between them. It’s best to seek personalized advice from a healthcare professional or registered dietitian.


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2 Weinheimer, E. M., Sands, L. P., & Campbell, W. W. (2010). A systematic review of the separate and combined effects of energy restriction and exercise on fat-free mass in middle-aged and older adults: Implications for sarcopenic obesity. Nutrition Reviews, 68(7), 375-388. https://doi.org/10.1111/j.1753-4887.2010.00298.x

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5 Rigamonti, A. E., Leoncini, R., Casnici, C., Marelli, O., De Col, A., Tamini, S., Lucchetti, E., Cicolini, S., Abbruzzese, L., Cella, S. G., & Sartorio, A. (2019). Whey Proteins Reduce Appetite, Stimulate Anorexigenic Gastrointestinal Peptides and Improve Glucometabolic Homeostasis in Young Obese Women. Nutrients, 11(2), 247. https://doi.org/10.3390/nu11020247

6 Baer, D. J., Stote, K. S., Paul, D. R., Harris, G. K., Rumpler, W. V., & Clevidence, B. A. (2011). Whey Protein but Not Soy Protein Supplementation Alters Body Weight and Composition in Free-Living Overweight and Obese Adults,. The Journal of Nutrition, 141(8), 1489-1494. https://doi.org/10.3945/jn.111.139840

7 Fonseca, D. C., Sala, P., de Azevedo Muner Ferreira, B., Reis, J., Torrinhas, R. S., Bendavid, I., & Linetzky Waitzberg, D. (2018). Body weight control and energy expenditure. Clinical Nutrition Experimental, 20, 55-59. https://doi.org/10.1016/j.yclnex.2018.04.001

8 Chae-Been Kim, Hyoung-Su Park, Hye-Jin Kim, Hong-Soo Kim, Jung-Jun Park. (2023) Does whey protein supplementation during resistance exercise have additional benefits for decreasing hepatic fat content?. Journal of the International Society of Sports Nutrition 20:1.

9 Amirani, E., Milajerdi, A., Reiner, Ž. et al. Effects of whey protein on glycemic control and serum lipoproteins in patients with metabolic syndrome and related conditions: a systematic review and meta-analysis of randomized controlled clinical trials. Lipids Health Dis 19, 209 (2020). https://doi.org/10.1186/s12944-020-01384-7

10 Pontes, T. de C., Fernandes Filho, G. M. C., Trindade, A. de S. P., & Sobral Filho, J. F.. (2013). Incidence of acne vulgaris in young adult users of protein-calorie supplements in the city of João Pessoa – PB. Anais Brasileiros De Dermatologia, 88(6), 907–912. https://doi.org/10.1590/abd1806-4841.20132024

11 Edwards CW, Younus MA. Cow Milk Allergy. [Updated 2022 Jun 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK542243/

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13 Paddon-Jones D, Westman E, Mattes RD, Wolfe RR, Astrup A, Westerterp-Plantenga M. Protein, weight management, and satiety. Am J Clin Nutr. 2008 May;87(5):1558S-1561S. doi: 10.1093/ajcn/87.5.1558S. PMID: 18469287.

14 Logan, S. L., & Spriet, L. L. (2015). Omega-3 Fatty Acid Supplementation for 12 Weeks Increases Resting and Exercise Metabolic Rate in Healthy Community-Dwelling Older Females. PLoS ONE, 10(12). https://doi.org/10.1371/journal.pone.0144828

15 Mori, T. A., Bao, D. Q., Burke, V., Puddey, I. B., Watts, G. F., & Beilin, L. J. (1999). Dietary fish as a major component of a weight-loss diet: Effect on serum lipids, glucose, and insulin metabolism in overweight hypertensive subjects. The American Journal of Clinical Nutrition, 70(5), 817-825. https://doi.org/10.1093/ajcn/70.5.817

16 Kemp DC, Kwon JY. Fish and Shellfish-Derived Anti-Inflammatory Protein Products: Properties and Mechanisms. Molecules. 2021 May 27;26(11):3225. doi: 10.3390/molecules26113225. PMID: 34072134; PMCID: PMC8198112.

17 Dighriri, I. M., Alsubaie, A. M., Hakami, F. M., Hamithi, D. M., Alshekh, M. M., Khobrani, F. A., Dalak, F. E., Hakami, A. A., Alsueaadi, E. H., Alsaawi, L. S., Alshammari, S. F., Alqahtani, A. S., Alawi, I. A., Aljuaid, A. A., & Tawhari, M. Q. (2022). Effects of Omega-3 Polyunsaturated Fatty Acids on Brain Functions: A Systematic Review. Cureus, 14(10). https://doi.org/10.7759/cureus.30091

18 WebMD Editorial Contributors. (n.d.). What You Need to Know About Mercury in Fish and Shellfish. WebMD. https://www.webmd.com/diet/mercury-in-fish

19 Fish Allergy | Causes, Symptoms & Treatment | ACAAI Public Website. (2022, April 14). ACAAI Public Website. https://acaai.org/allergies/allergic-conditions/food/fish/

20 Department of Health & Human Services. (n.d.). Shellfish and fish allergies. Better Health Channel. https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/shellfish-and-fish-allergies

21 Iwamoto M, Ayers T, Mahon BE, Swerdlow DL. Epidemiology of seafood-associated infections in the United States. Clin Microbiol Rev. 2010 Apr;23(2):399-411. doi: 10.1128/CMR.00059-09. PMID: 20375359; PMCID: PMC2863362.

22 Scombroid Fish Poisoning – MN Dept. of Health. (n.d.). https://www.health.state.mn.us/diseases/scombroid/index.html

23 Pugle, M. (2022). Tuna and Gout: Pros, Cons, and Tips. Verywell Health. https://www.verywellhealth.com/tuna-and-gout-5093006


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