Mark Gilbert BSc (Nutrition)
Mark is an expert in sports nutrition and dietary supplements. He has over 20 years of experience working with the biggest names in the bodybuilding industry.
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Are low-carb diets unhealthy? Should I mix Whey with milk?

QUESTION: I’ve just heard about a study done by Harvard Scientists that says low carb diets that are high in meat are very unhealthy. This is exactly the kind of diet I follow when I’m trying to get lean. Am I messing with my health here?

ANSWER. The available scientific research clearly shows that, on the whole, low-carb diets perform better at burning fat and preserving muscle than higher-carb diets - especially if they're high in protein. They also perform as well, and in many cases better, when it comes to improving risk factors for heart and vascular disease. Doubtless they would perform even better than that if they included more veg, some fruit and healthy fats, etc! The study from Harvard has concluded that "low-carb diets" higher in meat are less healthy than low-carb diets with less meat and more vegetables. So what's going on here? Have I got it wrong all these years? Am I going to be advocating eating soy burgers, Quorn (don't ask) and lentil stew? Am I going to convert my barbecue into a planter and grow petunias? Well, not quite yet, because as you may have noticed, there is a tiny note of sarcasm in my preceding comments. You see, I smelt a rat from the moment I read the title of this study and this rat is even stinkier than usual! Let's look at the facts:   Firstly, there's the fact that the biggest scientific review ever done on the subject (also from Harvard and done on "2 million" subjects) has already proven that meat isn't unhealthy, see:

This might piss you off (it made me furious to think how many people will be totally mislead by this), the "low-carb" group in this study were eating over 35% carbs!? THAT IS NOT A LOW-CARB DIET!!! Everyone knows high-fat diets don't work unless they're low in carbs - DUH!

Almost as outrageous is the fact that when the researchers played around with the results a bit, they noted that the meat group seemed to smoke more and exercise less and several scientists and others have questioned the way this study dealt with these types of risk factors that were unrelated to diet.

Most importantly, if you have any idea what you're doing and you value your health, you'll eat a moderate carb diet, with lots of healthy fats, low-GI carbs, vegetables and fruit (like my MuscleDiet Cutting Phase Diet) and if you do that, then this study doesn't apply to you anyhow. So all this study actually shows is that if you eat a slightly (and I mean "slightly") lower carb diet than the average slob, that's high in meat (and probably processed meat) and low in vegetables and fruit, it's probably less healthy than getting more of your calories from veg and fruit - wow, what a revelation! Therefore, those who trumpet the results of this study are either 1. Ignorant of the facts or 2. Unethical, it's really that simple.

QUESTION: I know a few big guys at my gym who mix all their whey shakes with milk. One guy even uses full-fat milk! Doesn’t this slow down protein absorption or damage the effects of the whey protein in some way? Also, is whey protein too quickly absorbed? I heard that it’s totally out of your system in like 2 hours?

ANSWER: I get this question in one form or another at least once a week! The answer is "yes but...". By "yes", I mean that mixing your "fast" (quickly absorbed) protein with milk (which contains mostly "slow" casein protein) won't slow down the absorption or affect the potency of the whey protein. You see, the casein just clots (forms clumps) in your stomach just as Mother Nature intended and then it gradually and slowly feeds its amino acids into your bloodstream to be available to the muscles over several hours (up to 7 or more hours according to careful studies that have tracked amino acid flux). The whey protein stays suspended in the fluid in your gut and is rapidly taken up into the blood so that very large amounts of amino acids are available to the muscle. To answer your second question, NO, research clearly shows that whey protein continues to deliver amino acids from the gut to your bloodstream for over 3 1/2 hours.

Now for the "but"...Be aware that every cup (250mL) of 2% (semi-skimmed) milk has about 120 calories, 8g protein, 12g carbs and 5g fat, so if you are trying to stay lean, you have to take account of these calories. If you are trying to gain and need extra calories, go with the cow juice!   

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