Meal Replacement Shakes - Why aren't they healthy to consume for all nutrition? [closed]

Question

In my research it seems properly made meal replacement shakes with fresh fruits and vegtables and balanced for proper nutrition are healthy as a possible replacement for one or two meals a day.

However from my perception there seems to be some consensus that consuming them all them time is not ideal and consuming them for every meal is bad. However, I am having trouble finding information on why.

Wouldn't a shake have almost all necessary nutrition? Is there something inherently bad with non-solid diets?

Is it because of the lack of nutrients that are usually only maintained from non-mixed ingredients like meats?

Is it healthy to continually consume meal replacement shakes over the course of the day vs. getting the recommended 6 meals a day?

Answer 1

I am pretty sure that the problem is not the fact that they are shakes. You could just put everything you would eat in a mixer instead and drink the result and I would assume that the result would be the same (maybe even a bit better since the meal is really well "chewed" which seems to be good).

The main problem you will have with ready made shakes is, that a lot of the phytochemicals in fruits and vegetables deteriorate pretty quickly once the cells have been destroyed. (And I am not talking about vitamins since those could be added pretty easily by supplementation).

Dietary fiber actually isn't a problem because you can add that very easily to a shake.

Honestly I think that you could live quite some time only drinking such shakes without having obvious malnutrition. But you can also live pretty long without eating any vegetables or fruit without having obvious malnutrition if you take vitamin supplements which doesn't mean it's a healthy behavior.

You should also consider, that making a shake that is truly nutritionally complete may just be pretty expensive and the result just might not be very tasty.

Answer 2

The reason is similar to why ready-cooked meals are not good for you - because they are processed and contain ingredients which are used to keep everything together for long periods of time.

e.g. if you cooked a lovely salmon steak, vegies and rice and put it in the fridge and then you bought the same ready-cooked meal and placed it in the fridge. Your home made meal would last far less time because the bought one contains special substances to keep it fresh which may and may not be good or necessary for you!

Also imagine you placed your home-cooked meal in it a blender and made it into a liquid food and then drank it you would not give your body enough time to process it and absorb the nutrients as it would flow through you system much faster.

Also if you placed that processed meal in the fridge you could only leave it there a few days - meal replacement drinks are in power form and can last months because they have ingredients to keep it from going bad.

Answer 3

I'd hazard a guess that it is to do with the healthy functioning of the colon

http://www.helpwithcooking.com/nutrition-information/dietary-fibre.html

Answer 4

Use a meal replacement shakes for no over 2 meals, or one meal and one snack, per day, unless you are closely supervised by your doctor.

Choose meal replacements shakes that contain a minimum of two hundred calories. They ought to even have a balance of carbohydrates, proteins and fats to produce adequate nutrition and reduce between-meal munchies.