12am and the alarm beeps. Time to take a creatinine-rich protein shake. Back to sleep. Beep...Beep...Beep. 5am, still dark, time to wake up and hydrate. Stovetop porridge for breakfast with an added scoop of protein powder and 75g of blueberries. All measured out the night before. Now off to the gym before work. 6am, focused and energised for leg day with the help of my trusty pre-workout friend. Squat deep! Push though the lactic acid burn! One more REP! PUSH! NEW PB! Rest.... you have earnt some mirror time and a protein shake.
A passage from the life of a modern day ‘work-out-aholic’. Gone are the days where a run around the block and a glass of milk is the typical fitness regime. Now in order to fit more snuggly into skin-tight shirts, the humble glass of milk is accompanied with whey protein powder – a derivative from milk itself. These days, the sounds you hear whilst wandering through a gym are just as likely to be coming from rattling protein shakers than clanking of weights.
Protein makes you bigger, stronger and healthier, right? “Protein is one of the key macronutrients, along with carbohydrates and fats, and is a crucial component of all cells in the body,” says Alice Disher, APD at the Australian Institute of Sport. It forms the building blocks of all bone, muscle, skin and blood. For all gym goers, it assists in building muscle and repairing tissue. You might be thinking, ‘well I should be able to eat as much as I want - the more the better, right?’. But like most things in life, too much of a good thing can be harmful.
Where do I find the best sources of protein?
Protein is generally found in animal sources (meat, eggs, poultry and fish). Other calcium-rich animal sources (dairy products such as milk, yoghurt and cheese) also contribute to your overall intake of dietary protein. Protein and calcium are also found in some plant sources, such as green leafy vegetables, nuts, seeds, grains and legumes. Other significant food sources are protein supplements, including powders and bars.
How much protein and calcium do I need?
It is recommended that protein should make up no more than 1.5g per kilogram of bodyweight each day. So for an 80kg man that is less than 120g per day. Each day adult men should consume 1000mg of calcium a day. Let’s put that amount it into perspective: that is around 2 glasses of milk, 1 tub of yoghurt and a protein shake. The daily calcium intake should not exceed 2500mg, or over 8 glasses of milk. That might seem like a lot, however in the gym and the fitness world, this is not uncommon. When working with even elite athletes Disher says protein and calcium can be easily reached with a health balanced diet, “Like the rest of the population, athletes require comparable amounts of protein and calcium to meet their training demands.” She goes on to say “Only in scenarios where energy balance is mismatched would these requirements begin to increase. This typically occurs in elite endurance. Even in these circumstances, any more than 1.7g/kg/day of protein would elicit no additional benefit. While higher calcium requirements are very much dependent on the energy availability and bone density of the individual”.
What are the health impacts?
It can be quiet easy to consume above the recommendations of protein and calcium per day. You would smash your daily intake if you ate two serves of meat, a protein shake, a protein bar and some yoghurt. High protein intakes, usually from animal sources (dairy and meat) can result in a variety of health effects - from increased dietary fat intake, to kidney stones. Excessive protein consumption can leach calcium from the bones and increase the amount of calcium excreted through urine. This can have significant impacts upon athletes, as it can increase their risk of brittle bones and even lead to osteoporosis.
Most people associate calcium with healthy bones and teeth, however it has several other benefits. Not only does it improve your blood’s ability to clot, it also assists in maintaining a healthy weight. On the other hand, too much calcium can increase the risk of kidney stones and constipation. Excessive intakes of calcium can also lead to a decreased absorption of iron and zinc.
In the gym environment, protein shakes are typically made by mixing whey protein powder with skim milk. Therefore, they are a vehicle for potential excessive intakes of protein and calcium. A single scoop (40g) of most protein powders contain as much as 20% of your daily calcium needs. Add some milk to the mix, have a shake pre and post your workout and suddenly both your protein and calcium intakes are shooting through the roof. A recent study published in The American Journal of Clinical Nutrition linked high dietary calcium, particularly from cow’s milk, with an increased risk of developing prostate cancer. According to the Australian Institute of Health and Welfare, in 2012, prostate cancer was the most commonly diagnosed cancer. This year, it is estimated that 1 in 4 new male cancer diagnoses will be prostate cancer, and about 1 in 10 of these will unfortunately die.