We’ve taken a critical look at 5 of the most common misconceptions about nutrition, and used solid science and sound logic to disprove them – so that you can be sure you’re getting the most of your diet and nutrition.

1. You have to have protein 20 minutes after working out

 Heard of the mythical ‘20 Minute Anabolic Window’? This misconception is one of the biggest around, and it suggests that your body is at its most anabolic (muscle-building) 20 minutes after working out. As a result, you absolutely have to drink a protein shake as soon as you put down your barbell, otherwise your gains will disappear. If you’ve ever worried about this myth (and when I started out, I did), don’t worry – we can undeniably disprove it in two simple points:

a. Protein shakes can’t be digested in 20 minutes. Protein is a complex chain of molecules, and for the body to use it in muscle growth, it has to be broken down into its component parts – BCAAs. This process takes hours, not minutes. Drinking a protein shake straight after working out will provide your muscles with useable BCAAs 1-8 hours later, depending on the type of protein you use. In other words, your muscles get no amino acids during the 20 minute anabolic window.

b. The body’s anabolic response to weightlifting is heightened for hours after working out, peaking at close to 3 hours post-workout. 20-minutes after leaving the gym, your body will be slightly more anabolic than normal – but it’ll be even more anabolic 1, 2 and 3 hours later. Drinking a protein shake anytime up to a day after working out will still benefit your body – and actually, ingesting BCAAs before working out will boost your anabolic response more than anything.

2. You need 30,000g of protein each day

I may have slightly exaggerated this myth – but in reality, some of the ‘recommended protein requirements’ claimed by bodybuilders are almost as ridiculous. So why does this misconception exist? Because no-one really knows the answer. Protein requirements for athletes vary hugely based on dozens of factors; including height, weight, lean body mass, daily activity levels, desired goals, chosen sport and drug use. A 300lb drug-taking pro-bodybuilder is going to require a whole lot more protein than a 160lb casual weightlifter, so listening to their recommendations isn’t always wise.

So how much protein should you have each day? As a general rule, aiming for 1g of protein per lb of body weight will be more than enough to make solid gains, but you can always increase this if your budget allows it. There’s nothing seriously wrong with overeating protein – but it will cost a lot, play havoc with your digestive system, and probably bore the sense out of you.

3. You need to eat little and often

Many people believe that eating lots of small meals will ‘boost’ the metabolism more than fewer large meals. In doing so, they hope that their body will use up more calories throughout the day. Sadly, this is just not true. In reality, it’s the total calories consumed that affect the metabolism.

Eating six 450kcal throughout the day will use up as much metabolic energy in digestion as eating three 900kcal meals – because they both contain 2700kcal. The meal frequency will affect the peaks and troughs of metabolic function (with fewer meals causing fewer large, longer-lasting boosts, and smaller meals causing more small, short increases), but the net result will be the same. In other words, meal frequency has no impact on the metabolism.

4. Fast food is the devil

Health and fitness culture takes a pretty extreme stance when it comes to fast food – generally suggesting that if you eat it, you’ll immediately gain 50lbs of fat and develop several heart diseases. The evils of ‘cheat meals’ are preached by bodybuilders the world over, and lifters as iconic as The Rock have actually advocated 150 days straight of clean eating. It’s true that fast food typically contains a ton of saturated fat and calories, and very little in the way of nutrition – but so what? Unless you’re eating fast food on a regular basis, it won’t have any detrimental effects on your health – and actually, it may have a beneficial effect on your mental health.

Objectively, a calorie from a cheeseburger is the same as a calorie from celery – they’re both just a unit of energy measurement. As long as you’re tracking your total calorie intake and macronutrient ratios, and getting enough nutrients from your total diet, you can include fast food in your diet without any detrimental effects. ‘If It Fits Your Macros’ (IIFYM) is a divisive dieting style that worries about total calories and macronutrients, and allows fast food consumption if it fits into weekly calorie and macro totals. Not only are these lifters able to enjoy the occasional burger and taco without being immediately wracked by guilt, but they’re able to get incredibly lean and muscular in the process. Why? Because a calorie is a calorie, regardless of where it comes from.

5. Eating too little causes starvation mode

‘Starvation mode’ sounds terrifying right? According to this misconception, if you stop eating regularly, or reduce your calorie intake by too much, your body will stop losing weight, and actually start to gain weight. This is an apparent throwback to a time when it was harder to hunt and find food, and this mechanism stopped us from keeling over and dying.

Not even a little bit true. As long as calories consumed are less than calories expended, you’ll lose weight. It’s not even up for debate – it’s just physics. The energy used by your body for movement and biological function has to come from somewhere. Your body finds energy by digesting food, fat, and when they both run out, muscle. Extreme dieting won’t cause you to gain weight, but you will see diminishing returns – and as your body turns to less effective energy supplies, your weight loss will slow down.