You've been told over and over again if you want to get anywhere near a flat stomach or a six-pack, you have to watch what you eat - namely, up the protein and stay away from the pizza. Difficult to implement, but incredibly satisfying to achieve.

While you may have just gotten the hang of tracking your macros, you may need to stop, especially if you're a man of a certain age. A new study has found that middle-aged men who follow high-protein diets may be at higher risk of heart failure.

Middle-aged men who follow high-protein diets, such as the Atkins, keto or paleo diet may be at risk according to a study published in Circulation: Heart Failure, an American Heart Association journal. The experiment surveyed 2,441 men aged between 42 and 60 for an average period of 22 years. Over the course of the study, 334 cases of heart failure - when the body is unable to pump enough blood and oxygen to remain healthy - were diagnosed.

The researchers divided the participants into four groups based on the types of protein they consumed on a daily basis. They found that the men who ate the most animal protein and dairy were at a higher risk - 43 percent and 49 percent respectively - of developing heart failure than those who ate the least.

The men who ate all sources of protein were at a 33 percent higher risk, while those who consumed plant protein had a 17 percent risk. The study doesn't indicate, however, if the plant protein is strictly natural (vegetables, legumes, etc) or down to supplements as well.

Higher intake of protein from most dietary sources was associated with slightly higher risk, the researchers said, adding that only proteins from fish and eggs were not associated with heart failure risk in this study.

"As many people seem to take the health benefits of high protein diets for granted, it is important to make clear the possible risks and benefits of these diets," said Dr Jyrki Virtanen, study author and an adjunct professor of nutritional epidemiology at the University of Eastern Finland.

He added that earlier studies have linked diets high in protein - especially from animal sources - with increased risks of Type 2 diabetes and even death. A lot of people take the concept of a high protein diet and run away with it, eating ridiculous things that are nowhere near healthy.

The authors of the study concluded that as there is currently little research on the link between dietary protein and heart failure risk, further research is needed before they can say that moderating protein intake would help to prevent it.

A separate study that was recently presented at the World Congress on Acute Heart Failure in Vienna found that eating protein can help patients with heart failure to live longer - quite the opposite result.

As with most studies, several of them need to be done to really cement the theories they hypothesize. While it's accuracy is still debated, do your best to eat a balanced diet or seek medical help if you decided to embark on a trendy diet.

With the chilly arrival of December, most people are settling nicely into their winter bods. However, others are still valiantly avoiding the excessive amount of sweet treats available, instead drinking protein shake after protein shake after hitting the gym.

But one personal trainer is here to tell you that protein drinks are not the one. Max Lowery, who created the Two Meal Day intermittent fasting plan, revealed this year why he has never taken a protein shake in his life - and why he doesn't intend to in the future.

Talking to Business Insider in June, the 28-year-old claimed that the average person gets all the protein they need from eating real food, and insisted that the drinks are unnecessary for about 90 per cent of people looking to get fit.

"The only people who might benefit from them are vegans who aren't being so careful with their diets — so it's an easy way to get some protein — or elite athletes who are training twice a day six days a week," he said.

"The average untrained person needs as little as 60-75g of protein and the average trained person who exercises three times a week needs 1.2g-2g per kilo of body weight. You can easily get enough protein from eating real food. In fact, too much protein can actually be broken down into sugars that create an insulin response which can facilitate fat storage. This is called gluconeogenesis."

In addition, the muscley fitness expert pointed out to Business Insider that the ingredients in protein shakes may not always be the best things for your body.

"Lots of shakes are packed with artificial sweeteners like corn syrup solids, sucralose, and acesulfame potassium —companies use these because they are addictive and send a signal to the brain to keep drinking or eating without an off switch — even if they, themselves, don't contain any calories," he said.

Continuing, Lowey - who was a professional sprinter for four years - claimed that the producers of these shakes often use these sweeteners to cover other unsavoury tastes.

He said: "A lot of whey protein comes from very poor sources as well, most commercial whey powders are high-heat-treated, acid-flushed, and stripped of vital nutrients, creating an imbalanced, acidic 'whey isolat,' that's frequently contaminated with synthetic additives, chemical detergents, and heavy metals. It's no wonder they have to use all these sweeteners to cover the taste."

Blasting the multi-million-pound industry for its "clever marketing" and celebrity advocates, the personal trainer also added that several "unbiased" studies have suggested that protein consumption over the course of the day is what really matters.

So, will you be steering clear of protein shakes after this advice from a seasoned fitness buff?

Warning: the article below contains content some readers may find distressing.

A man who only drank water for 30 days has revealed the terrifying effects it had on his body.

While fasting is a practice that goes back thousands of years, most people only end up going without food for a number of hours at a time, rather than days on end.

Going without any food for numerous days is something health professionals advise against, as it could have serious health consequences and in extreme cases even lead to death.

According to VeryWell Health, experts indicate that people begin to become weak after 30 to 50 days without food, and can die in 43 to 70 days.

How soon a person succumbs to the effects of not eating vary from person to person, with many factor affecting it including sex, age, their starting weight, as well as the amount of water they are intaking.

The body fights starvation by producing glucose and breaking down fatty tissue, before moving on to breaking down muscle before a person ultimately dies from lack of food.

Despite the warnings, one social media user documented their attempt to go 1,000 hours without food - or 42 days - but ended up finishing their challenge early after 30 days.

X (formerly known as Twitter) user @maru.eth charted their progress after giving up food over Christmas, until they broke their fast on January 23 after 30 days.

He posted on December 26, at the start of the challenge: "Updating this thread with my 1000-hour (42 days) water fast progress that I started after Christmas dinner.

"I'll only drink water and supplement electrolytes (sodium, magnesium, potassium)."

The man, who is 6'4" tall, revealed that his weight on December 24 was 97.85kg (216lbs).

He then shared regular updates on how the water fast was going, revealing that the first 72 hours were the hardest as he felt the most hunger pangs during this time.

He explained: "The first 72h are the toughest because your body is constantly signaling you to eat. it gets way easier after that initial period."

After a week, he revealed that he had dropped to 92kg (203lbs), but struggled to stick to the regime over the New Year celebration.

He explained: "Spending NYE without any yummy snacks or drinks was tough, but I made it, I'm alive.

"Slept pretty well and feeling good overall, but I can't shake off the feeling that this fast feels considerably different than my other ones... somethings up and I'm not exactly sure what."

He added that while he never found sleeping difficult, the morning were "rough", adding: "I lose approximately 300g each day if I keep my sodium intake constant. I still lost actual fat but you don't see that on the scale because of increased water retention."

Of course, if a person is not consuming any food, one might assume that they would stop needing to poop, too.

However, despite not having eaten anything, @maru.eth revealed that he was still producing some excrement almost two weeks after existing on only water.

He explained that his stool was "very long and that there's residue coming out even after 13 days of not eating anything", and on January 17 revealed that he'd had his first poop in 12 days.

He revealed: "need to log this. I just pooped for the first time in 12 days. consistency was not at all what I had expected. regular logs, almost a normal amount of poop as well. where is this coming from? it's crazy how much stuff can still accumulate from the colon..."

Towards the end of the fast, he reported noticing a "serious decline in mental capacity" meaning he could "no longer trust [his] decision-making".

On January 23, he revealed that he was ending his feat early, having dropped an enormous 15kg (33lbs), and now weighing 82.9kg (183lbs) - and vowed never to attempt something so extreme again.

He told his followers: "I'm finally done. 30 days without food, just water.

"I didn't quite reach the 1000 hour mark as I initially planned but I'm still proud I kept at it for so long. I did this to challenge myself and for no other reason! never fasting for so long ever again."

He also revealed that he'd broken his fast with a small bowl of soup, as the body needs time to readjust to eating small portions again, rather than overloading with a large meal in one go.

Needless to say, this is definitely not something anyone should ever emulate as the risks far outweigh any perceived benefits, and the electrolytes in the body must be kept within safe parameters.

The best advice from medical professionals is to maintain a healthy, balanced diet and incorporate exercise into your daily life to ensure you live a long and healthy life.

If you or someone you know is battling an eating disorder, please get in touch with the National Eating Disorders Association's helpline at (800) 931-2237 or visit https://www.nationaleatingdisorders.org/help-support/contact-helpline

Featured image credit: Viktoriya Skorikova/Getty Images

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