When you are older, ten, twenty, or thirty years down the line, the sum of all the lifestyle decisions you made within that time frame can heavily influence your health.

The amount of protein you take in every day can promote healthy ageing.

How much protein should I be aiming to get every single day and why? I'll try my best to answer that here, and focus on the 'why' because it's very important.

I think there is a misconception with protein in that many people think if they consume it in relatively large amounts they will become more muscular and bulky looking. This view is incorrect. Muscle mass is built through weight training and the mechanisms that are influenced by that cause growth. Even then it is very, very difficult and takes a huge amount of work over long periods of time to achieve a body you would like, let alone to become 'too muscular'.

I like the analogy of me dropping a football at your feet and asking you to kick it off the wall. Your answer is 'I don't want to do that in case I end up scoring in the last minute of the Champions League final in May'.

Don't worry about things that will never happen, especially things that are holding you back from making positive changes to your health. The supplement whey protein is a derivative of cheese production so it's like holding the opinion that if you consume too much cheese every day you'll magically sprout muscle.

If only it were that simple.

It's the same with protein from any other food source, in isolation your intake it is not responsible for muscle growth. But how much should we be taking in daily if we train or don't train?

When it comes to protein intake day to day the current recommended intakes we are told to go by are behind some of the newer, more up to date research which has come to light mostly from the area of sports performance. We can take these guidelines and apply them to general populations as well because of the impact on muscle mass and it's positive effect on health.

The European Food Safety Authority's current recommendations (as of 2015) for adult protein intake per day is 0.83 grams of protein per kg of bodyweight per day.

There's nothing wrong with this recommendation. It is aimed at the general population and that's perfect, but the assumption is they don't partake in resistance training.

Now, health, well-being and nutrition is a vastly complex area. What I'm going to do here is point toward some information which is more apt for people who train. I believe everyone should train, and by train I mean do some form of resistance training and cardio 3-5 times per week for the huge health benefits (heart health, bone health, mental health, blood glucose control, management of body weight, muscle growth/retention, the list is long).

The resistance training is the foundation of health promotion and the protein intake complements/supports it.

My bias is that I believe everyone should train to promote their health and these protein guidelines relate to that. There's no harm in someone who doesn't train following them as well. Protein based foods generally make people feel fuller for longer so can help a huge amount in weight management too.

If we look at the International Society of Sports Nutrition's position stand (as of 2017) on protein intake we see the guidelines fall between 1.4 and 2 grams of protein per kg of bodyweight per day for exercising individuals.


Let's look at the difference between the two recommendations for a typical female who weighs 70 kg.

There's quite a reasonable difference between the two both numerically and in practical terms. When it comes to how much actual food you need to eat every day there's a huge gap to bridge between 0.83 grams and 2 grams  per kg of body weight per day as it's more than twice the amount to reach the higher end.

The difference between these two recommendations is significant.

Is the EFSA incorrect? No.

Is the ISSN guideline more up to date and applicable to populations who partake in resistance training and exercise and who want to maximise the benefits? Yes.

Could people who don't train benefit from even aiming for the lower end of the ISSN guideline? Yes.

Something that comes up a lot is 'what source of protein is best?'. I'll deal with toward the end of this piece, but firstly I'd like to work through some of the health implications that occur as we age and how protein can influence them.

I hope to explain the 'why' when it comes to exercise (weights/cardio) and aiming toward the ISSN guideline.

As you can see I'm big on training so it really will be on the benefits of the synergy between protein intake/weight training.

If I had to summarise the BEST advice possible to give to someone about looking their best and promoting healthy ageing and longevity it would be this; 

‘Manage your weight, stay as lean as you comfortably can (minimise excess fat around  your midline). Exercise regularly, get strong, and eat well balanced, healthy diet with LOTS of vegetables/fruits/greens and adequate protein’.

We've established our numbers on adequate protein so let's take a look at the health/ageing considerations it and how we can influence it.

Sarcopenia.

I'm going to use many references here from a study by McLeod et al (2015) titled 'Live long and prosper: the importance of skeletal muscle strength for healthy ageing' to run through this.

Why is skeletal muscle so important?

'Skeletal muscle helps maintain posture, breathing and locomotion, but is also an important nutrient store and metabolic regulator. It is attached to bone and is what facilitates movement, so you can see where this debilitates then problems will occur. As we age, it gets harder and harder to retain muscle unless you’re doing the right things. During ageing approximately 30% of peak muscle mass is lost by 80 years, this is compounded by physical inactivity and poor nutrition. Loss of skeletal muscle mass can result in impaired locomotion function, compromised balance and increased risk of osteoarthritis and falls/fractures'.

This deleterious loss of muscle mass as we age is known as sarcopenia. It's a case of 'use it or lose it'. If you are not exposing your muscle tissue to some kind of stimulus then it will lose function.

This muscle wastage can have a downward spiral effect on a person's health. It is linked to functional decline, frailty, falls, and mortality. A person is more likely to fall, to suffer a bad outcome from the fall and a host of negative outcomes associated with that, and in turn dying earlier.

If you look at the image below taken from the McLeod study you can see MRI imagery depicting muscle mass from three subjects. From left to right first is a male aged 24 (who is quite lean) has plenty of muscle mass (the dark grey). The middle picture shows the large loss of muscle mass of a 66 year old inactive male, and finally the picture on the right also shows a 66 year old male but who was active and retained muscle mass. 

You lose muscle mass as you age, this is an inevitable part of the ageing process. Losing muscle mass can result in negative health outcomes.

Is it possible to hang on to muscle mass as we age and prevent the loss?

YES, You can retain muscle mass as you age through exercise and weight training. Providing a stimulus to your muscle tissue helps it grow and at the very least helps sustain it.

Adequate protein intake plays a role here as well, as while the training influences the structure of muscle tissue, protein is needed to optimise that change. Inadequate protein intake, that which is below what the current research points toward (the ISSN guideline) sells you short of your efforts.

This stuff is important because there’s no easy way around it, there’s no pill you can buy. A final quote from the McLeod study, ‘Pharmalogical interventions aimed to slow the progression of, or reverse sarcopenia, have generally been unsuccessful’.

We move on to something very closely related to declining muscle as we age, bone mass.

Bone Mineral Density.

You may or may not be familiar with the term osteoporosis. It is defined as a systemic skeletal disease characterised by low bone mineral density or bone mass. Your muscle tissue declines as you age, guess what? Your bone mineral density does too.

Have a look at the chart below. You'll see that we reach peak bone mass in our thirties but after that it declines, and the decline is greater in women once they reach menopause.

Again, like sarcopenia, osteporosis is associated with a downward spiral of health effects. You are more at risk of falls. You are more at risk of breaking something when you do fall, the recovery time is much longer and more difficult than if you had stronger bones (and more muscle mass).

Weight training and exercise can help prevent this decline. As with sarcopenia and muscle tissue, weight training provides the stimulus or resistance your bones need to become more dense and to retain that density as you age.

The effect of protein intake here isn't as profound as with the mechanisms of muscle growth, but let's assume that maybe some of your intake comes from dairy sources as you're trying to take more in and trying to get it from quality sources (dairy is a great source of quality protein). This may push up your calcium intake which in turn can have a positive effect on bone mineral density.

There's a cluster of positive effects adequate protein intake and training can have on muscle mass and bone health. 

For anyone who is reading this in their mid thirties or younger, you should be doing your utmost to make sure your peak bone mass is as high as you can possibly get it. Stronger, denser bones earlier in life will stand to you as you age.

Remember the picture with the muscle mass of the 24 year old and the two 66 year old males? If we jump back to that study here's an interesting quote.

'By 2050 one quarter of Europe’s population will be over 65, representing a 10% rise in half a century. This leads to an increase in the prevalence of ageing related diseases and the associated healthcare expenditure’.

In 2017 figures from the Central Statistics Office here showed a nearly 20% rise in population aged over 65 between 2011 and 2017. 'The average age of the Republic’s population rose by 16 months to 37.4 years between 2011 and last year’s census'. The group aged 65 and over grew by almost one-fifth, 19.1%, over the same period, making it the fastest-growing sector.’

We've established how beneficial this can be on a personal level, but it goes beyond that. Collectively, this can affect our healthcare system as well. In Ireland we can see we are living longer, but if it's not necessarily 'living better for longer' then we face a huge strain on the healthcare system from what is a very preventable problem.

The Importance Of Strength And Fitness.

Without straying too far off track from the title of the article, I'd like to take a quick look at strength and fitness and how it relates to mortality.

The following graph shows data from a study by Ruiz et al (2008) titled 'The association between muscular strength and mortality in men'. It had 8,000 participants reviewed over an 18 year period to assess the influence of muscle strength and cardio-respiratory fitness on healthy ageing.

The higher the bar, the higher the mortality rate.

Participants who were over 60 years old and in the lower third for strength were 50% more likely to die from all cause mortality than the upper third. The same statistics applied to death from cancer. Similarly, individuals with higher cardio-respiratory fitness had greater life expectancy than those with low levels.

The bottom line is that if you are strong and fit you’ll live longer than if you are weak and unfit.

Protein Considerations For The Elderly.

Before I wrap things up I do want to shine a light on the fact that as we age we become less sensitive to the effects of protein in terms of muscle retention. It's a piece for another day, but basically the ISSN guidelines of 1.4 - 2 grams per kg of body weight are what elderly populations should be aiming for and with larger servings of protein per meal.

As we age our bodies become less sensitive to the effect protein has on stimulating muscle growth and retention so bigger feedings are needed (Moore et al 2015).

So while we are ageing and may want to look after ourselves, if we know anyone who is elderly these are some guidelines which may help.

What Protein Source Is Best?

I haven't forgotten that I said I'd address this. Animal and dairy sources of protein have a complete amino acid profile which means they technically are better by default as their chemical structure makes them optimal for supporting muscle growth.

Plant sources are incomplete proteins and have lower bioavailabity meaning less nutrients are taken up.

Think of one protein serving like building a shed. Animal protein means you have all the tools you need and you have the ability to use every single one of them.

Plant protein means you don't have all the tools you need and more than one delivery, possibly several deliveries of tools may be needed for the same thing to happen.

This is down to the chemical structure of the foods and how they interact with our bodies. Anyone who knows me as a coach knows I put a BIG push on plant intake because of the nutrients they provide for health, but when it comes to what is technically better (leaving morals and everything else aside) animal products win.

Can someone leave meat out and still hit their targets and support muscle growth? Yes. It takes more organisation and work.

If you don't want to eat meat or animal products for whatever reason that's absolutely fine, but technically they are the favourable source when it comes to aiding  muscle protein synthesis (the body's process of building muscle).  

Summary.

Protein is an ESSENTIAL macronutrient (we need it to survive). We also need adequate intake for the growth and/or maintenance of muscle mass and function, and by close association bone strength and density. The recommended intake guidelines are behind what the most the current research points toward, especially for people who train and the elderly.

There are many, many other physical and mental health benefits to lifting weights and looking after your nutrition (positive effects on sleep, anxiety, depression, blood glucose control, hypertension, cognitive decline). Along with adequate protein intake stronger, fitter people have been shown to live longer. 

How does your protein intake look?

Resources:

https://www.efsa.europa.eu/en/press/news/120209
https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0177-8
https://www-sciencedirect-com.ucd.idm.oclc.org/science/article/pii/S0140673619311389
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4889643/
https://www.ncbi.nlm.nih.gov/pubmed/30324412
https://www.rte.ie/news/ireland/2017/0706/888220-census-age-data/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2453303/
https://www.ncbi.nlm.nih.gov/pubmed/25056502