To eat steak, or not to eat steak?
It seems no two days are the same in the world of food, particularly when it comes to protein.
Global health authorities recommend around 46 grams of protein per day for women, paleo enthusiasts swear by at least 90, and vegans and vegetarians claim we’re eating far too much to begin with. But while us omnivores have been busy laughing at the purists, new research suggests our animal-loving friends may be onto something…
The purpose of protein
All humans require protein as part of our diet, as it’s one of the three macronutrients critical to helping our body complete its functional and structural mechanics. The amino acids which make up protein are broken down and pooled into our blood for later use when we eat protein-containing foods. These acids are then used when our body needs to build an enzyme or repair broken muscle tissue. Protein can be found in every cell of the body, especially muscles, and since our bodies can not store amino acids, they must be supplied via the food we eat.
Where it’s at
Protein can be found in a wide variety of plant and animal products. The US Department of Health and Human Services considers seafood, red meat, poultry and animal byproducts like milk and eggs, as well as plant sources like seeds, legumes, nuts and soy products as equally valuable sources of protein. However new research is beginning to suggest plant based sources may be superior.
According to nutritionist Julieanna Hever, when we consume protein from plant products, our body is able to more easily obtain the necessary amino acids as well as the specific minerals, vitamins, antioxidants, fiber and phytonutrients without saturated fat and cholesterol getting in the way.
“Animal proteins are wrapped up with unhealthy saturated fat and dietary cholesterol, and are very low in most vitamins and minerals,” asserts Hever.
“Humans need about 10 per cent of calories from protein. Virtually all whole plant foods contain at least this amount, so if you consume enough volume and variety of whole plant foods, your protein requirement will easily be met.”
All in the numbers
The Institute of Medicine recommends adults consume 10 to 35 per cent of their daily calories through protein sources. That equates to roughly 56 grams of protein a day for men and 46 for women, which you can get in a single serving of lentils or a couple of handfuls of black beans (nachos and chilli, we’re looking at you), so it’s relatively easy to achieve.
Too much of a good thing
According to accredited dietician, Robbie Clark, consuming high amounts of protein is not only unnecessary, but does not benefit us long term.
“There’s no nutritional advantage to using protein powders or shakes over high protein foods, and there’s a lot of controversy around whether or not diets like paleo are healthy or not…especially when it comes to the topic of longevity. The reason being, proteins and their amino acids regulate the two major pro-ageing pathways. Eating lots of protein seems to ‘up-regulate’ those pathways and leads to the promotion of higher rates of both death and disease,” explains Clark.
Excessive animal protein can also drain calcium resources in the body, spelling disaster for your bone health. Since calcium helps neutralize the acids found in animal based protein sources, and your bones are your body’s richest source of the stuff, chowing down on bacon and eggs for breakfast every day, as opposed to an alkaline plant-based protein brekkie like peanut butter on toast, can ultimately weaken your bones over time.
A Nurses Healthy Study actually found women who ate 95 grams of protein a day or more, were more likely to break a bone compared to women who ate less. As well as this, research conducted by the National Kidney Foundation found consuming more than the recommended daily amount of protein can place excessive stress on the kidneys and cause pre-existing problems and kidney stones to surface.
The pros of going low protein
A recent study carried out by scientists at Australian institution, University of Sydney’s Charles Perkin’s Centre, found interesting results relating to protein and its overall effect on our health. The team discovered reducing the amount of protein in our diets can actually drastically slow down our ageing process and increase our life expectancy, ultimately leaving us better off.
The team, led by academic director and report author, Professor Stephen Simpson, studied two sets of mice which were put on different diets: one fed a calorie-restricted diet and the other a low protein, high carb diet. The mice fed low protein, high carb diets were just as productive as those fed the low calorie diet, and had healthier hearts and better digestion.
A similar study conducted by the University of London’s Institute of Healthy Ageing found by reducing specific proteins, particularly those found in meat, fish and nuts, people should live a longer and healthier life.
Although high protein diets are becoming the norm, new scientific breakthroughs are proving they could be an unhealthy new fad worth addressing with a bit more scrutiny. Adopting a diet which includes a larger variety of high protein plant-based foods, similar to that of vegan and vegetarians, could be the most beneficial route to a longer, healthier life.
Before dramatically changing your diet, be sure to seek the advice of your GP or medical specialist.
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