The ultimate guide to whey protein

Protein shakes can make you think of large, unwieldy tubs of protein powder used by bodybuilders with massive muscles. But the truth is that protein is good for everybody.

Protein is a nutrient made up of amino acids, the ‘building blocks’ for muscle growth. You can find it in animal products such as meat, eggs and dairy or plant sources like nuts and beans.

But what about whey?

If you’re interested in learning more about this particular type of protein, you’re in the right place.

Skip to:

• Why we need whey protein
• How much whey protein a day
• When to use whey protein
• 8 whey protein benefits
• Whey protein side effects
• How to take whey protein

Why do I need whey protein?

Anyone who likes to keep fit, whether they do yoga, go on long walks or swim, needs protein to maintain their muscle mass and strength.

It also helps fill you up, which is excellent for weight loss and helps maintain healthy bones, muscles, hair, and skin.

Your body needs protein the most after a fitness session to help grow and maintain muscle fibres that tear during exercise. Whey protein is ideal, as the body quickly absorbs it.

But whey protein is much more useful than simply helping you get the most out of your workout.

How much whey protein a day?

Generally, most adults in the UK should be consuming around 0.75g of protein per kilogram of their body weight every day. This equates to about two portions of high protein foods like meat, fish or nuts, each day.²

If you decide to supplement your diet with whey protein, you should stick to a maximum of two protein shakes a day.³ 

But everyone is different, so the right amount of protein for you could be different than the next person.

Your daily protein intake can vary due to age, height, weight, and activity level. For instance, if you live a highly active lifestyle, your protein intake will likely need to be more than someone who is less active.

To figure out the right amount of protein for you, check with a doctor. They will be able to advise you on how much you should be consuming and stop you from getting too much or too little.

When to use whey protein?

It is thought that if you’re trying to maximise your muscle growth, the best time to use it is either immediately before, during or right after a workout.

This is because muscle synthesis is at its most effective in the time after exercise.^4,5,6,7

But you can take whey protein at any time of the day as your body is able to digest and metabolise whey protein quickly.

If you’re looking for a protein that will metabolise a bit slower, why not try casein?

Casein is a slow-release protein that feeds your body with essential amino acids over a longer period, making it best to take before you go to sleep.⁸

8 benefits of whey protein

So, is whey protein good for you? Well, we all know that we need protein in our diets to keep our bodies working as they should, but whey protein can feed your body with even more benefits.

Read on to find out our top 8 benefits of whey protein...

1. It can help you lose weight

Generally, an increased protein intake has been found to have a positive effect on weight loss in multiple scientific studies.^{9,10,11,12,13}

When looking at the link between weight loss and whey protein specifically, a study by the American College of Nutrition in 2014 found that simply swapping some sources of calories for whey protein (while also being consistent with weight training) can help you lose roughly 8 lbs. All while also helping you to gain lean muscle mass.¹⁴

If weight training isn’t your preferred exercise method, don’t worry.

Whey protein supplements have also been found to help people lose body fat and keep muscle mass while also being in a 500-calorie deficit every day.¹⁵

2. It can help you feel fuller for longer

You’ll be happy to hear about this benefit if you struggle with snacking and overeating.

Whey protein may also be better at stopping hunger pangs than other protein supplements.

In one Dutch study, those given whey-protein enriched breakfasts felt fuller for much longer than those who consumed soy or casein proteins instead.¹⁶

3. It boosts your immunity

Another potential benefit of the whey protein diet is its effect on your immune system.

Studies on rats in 2021 concluded that increased whey protein consumption might increase the immune response against antigen exposure and decrease the incidence of disease.¹⁷

Further studies on how whey protein can support the immune system in humans are needed.

4. It can improve heart health

Evidence from America reveals whey protein can improve insulin sensitivity, helping protect blood vessels from the damage associated with insulin resistance, and reducing the risk of heart disease.¹⁸

5. It aids in exercise recovery

The amino acids in whey protein are great for keeping your muscles healthy and strong.

The antioxidant glutathione – essential for fighting free radicals and protecting cells from damage – is lost during exercise.

But when cyclists were given whey powder supplements during Canadian trials, it prevented depletion of their glutathione levels, enabling them to recover more quickly than those given a placebo.¹⁹

6. It may improve your smile

Whey protein might even boost your pearly whites – as it contains a compound called glycomacropeptide (GMP). GMP helps inhibit the growth of plaque bacteria that cause dental decay, as well as binding to calcium in the mouth, boosting tooth remineralisation.

It’s time to say cheese, literally! ²⁰

7. It may lower blood pressure

Whey protein contains bioactive peptides found in dairy called ACE inhibitors (angiotensin-converting-enzyme inhibitors).^21,22

The inhibitors that are found specifically in whey protein are known as lactokinins.²¹

How does this relate to blood pressure, then?

Well, there have been several studies conducted on animals that have highlighted the positive effect that these lactokinins can have on lowering blood pressure – however, studies on this effect in humans are limited.^23,24

8. It may help reduce inflammation

While short-term inflammation is a natural bodily response to damage, chronic inflammation can be a lot more serious as it’s a risk factor for several different illnesses.

However, some evidence does suggest that consuming whey protein could help reduce inflammation.

An extensive review study from 2009 by Molecular Diversity Preservation International found that doses of 20g a day or more of whey protein supplements significantly reduced a key marker of inflammation – C-reactive protein.²⁵

Whey protein side effects

Whilst there are some great whey protein benefits, there are some things you should be aware of – particularly if you plan on consuming a fair amount!

The weigh-in on whey

• The whey protein diet is a great way to increase your protein levels in a quick and easy way
• It’s best to consume whey protein right before, during or after a workout to maximise its benefits
• Whey protein may be beneficial for weight loss, gaining muscle, supporting your immune system, supporting heart health, aiding exercise recovery
• It’s not advised for people with liver issues, it may make acne worse, and it may cause digestive upset

Last updated: 3 January 2023