Lets use an example - a guy wanting to build muscle, but has a full time job mon-fri. A common problem would be, not being able to get enough calories in throughout the day, and that's where meal replacements are great. It's easy to take a shaker with the powder into work and just add water or milk. They also come in handy for people that struggle to put on size.
Meal replacement shakes can also be known as 'mass gainers'. You can make them yourself or you can buy them. Making them yourself would be better, as you can put fresh food into them, rather than powder. But whether you are making it yourself or buying, you want to make sure you get a good one. Some meal replacements are cheap and cheap for a reason - they are made with more fats (usually not good fats!) and carbs, with less protein. That's not what you want. You want a good balance of protein carbs and fats. Depending on your requirements, the ratio's can be different. On average, a good shake for someone wanting to pack on muscle and size would have around 40-50g protein, 90-100g carbs and 25-35g fats (good fats!). On average, that shake would be - 830kcal. That is probably bang on average, as I have seen some topping 1000kcal and some at 600kcal. Again, it does depend on your goals, as some people might need more calories if they struggle to put on size. As I always say, try your best to get your calories from real food before turning to shakes. But if you are in the position of not being able to get fresh food in you, then a shake is the next best thing.
Now, some people seem to rely on these shakes and neglect real food, and that's a waste of time and money. Yes, the shakes contain protein, carbs and fats, but that's it. If you have a fresh healthy meal containing protein, carbs and fats, it will also contain a lot of other vitamins and minerals (which you don't have in the shakes). So try and stick to food where possible, but if you need help with your calorie intake, then go for a shake but check out the ingredients and ratio's of them. A good meal replacement/mass gainer is the 'hi-calorie mass gainer' from Hench Nutrition. (discount code - HNBKHM1H)
As mentioned above, there are 'diets' out there that are literally 3 shakes a day, and that's it! That is just insane, a waste of time and money, and a con. If you do that, you may well lose weight, but its not going to be mainly fat loss, and as soon as you start eating food again, the weight will come back. A meal replacement shake 'diet' is not sustainable, therefore it will not work long term. Stick to healthy, fresh nutrition, as that is sustainable and does work long term.
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