You may see fitness bloggers and PTs chugging down shakes every day, but that doesn’t mean you should, too. Scientists believe that daily protein shakes might be causing us to pile on the pounds.
Protein powders and snack bars are full of branch-chain amino acids (BCAAs), and these are essential for building and repairing muscle fibers. You have them after a session in the gym to help repair the muscles you’ve worked. But it turns out that chugging amino acids could have some negative side-effects.
Scientists from the University of Sydney’s Charles Perkins Centre have found that too many protein shakes and snacks may reduce our lifespan, make us moodier and lead to weight gain.
Dr Samantha Solon-Biet has been looking into how our food can impact on metabolic health, reproduction, appetite and aging.
High protein diets result in shorter lives
“While diets high in protein and low in carbohydrates were shown to be beneficial for reproductive function, they had detrimental effects for health in mid-late life, and also led to a shortened lifespan,” she explained.
“What this new research has shown is that amino acid balance is important—it’s best to vary sources of protein to ensure you’re getting the best amino acid balance.”
When we supplement with BCAAs that can lead to a high amount of the acids in our blood. They compete with something called tryptophan for transport to the brain.
We need tryptophan because it helps us to make the “happiness hormone” serotonin. Not only does serotonin make us happier, but it also helps us to sleep better and reduce appetite.
So if we’ve got a load of BCAAs pushing stopping that tryptophan from getting to the brain, we’ll start under producing serotonin.
Lack of serotonin results in overeating
“The serotonin decrease caused by excess BCAA intake led to massive overeating in our mice, which became hugely obese and lived shorter lives,” explained Professor Stephen Simpson.
Mice were fed double the normal amount of BCAAs, the standard amount, a half or one fifth for life. Those who were fed double increased their food intake, resulting in obesity and a shorter life.
The conclusion? Get your protein from a wide array of natural sources – not in powdered form.
Eat protein in food form – not powder
Lean meats, fish, eggs soy, hemp and peas all contain protein and amino acids, and come with added benefits like fibre, vitamins and minerals.
It’s really important to make sure that you’re eating different protein sources in order to get a variety of amino acids. And as well as protein, eating foods rich in tryptophan is important too.
That’ll result in a better quality of sleep, a potentially better mood and a controlled appetite. You can find it in seeds, nuts, soy beans, cheese, turkey and chicken.
By all means, have a protein shake if you’re short on time or you’re struggling to get enough protein via your diet (if you’re vegan, perhaps), but don’t rely on shakes as your primary source of nutrition.
This article originally appeared on The Sun and is republished here with permission.