Well, if you put the flaxseed in water overnight, in the morning you will have flaxseed water.
I have been told that it is like a gel and it has a light taste, not precisely pleasant. My neighbor lost his very prominent tummy by taking that drink for a few months. At the time the benefits of flaxseed were not commonly known.
Now we know that flaxseed contains omega 3 fatty acids, which are very important for our health. I think that is one of the reasons my neighbor lost weight. But there were other reasons too that I suspect, such as, he was drinking more water and no alcohol, and perhaps, the omega 3 gave him a sense of higher energy level and he became more active.
In any case, omega 3 is a very important nutrient and many bodybuilders recommend it, because according to them, it helps to burn fat and build muscle. Jorge Cruise, the fitness author, also recommends it for the same reasons.
If flaxseed does not sound appealing to you, another option is chia seeds. In Mexico and Central America, people drink chia seed water. It is made the same way and it is also like a gelatin. It has the same omega 3 that flaxseed has and it tastes better. Of course, if you like to enjoy chia seed drink, do not add sugar. You may use Stevia or other natural sweeteners. In Latin America, they add color to make the drink more attractive; this can be done just by adding a little bit of pomegranate juice or any other colorful juice.
Chia seeds do not go rancid and their gel can be used to thicken sauces also. Flaxseed goes rancid, on the other hand, and once it is old it is preferable not to use it.
Omega 3 fatty acids are very important even if you do no want to lose weight, because it helps to regulate the cholesterol levels. Omega 3 is also very good for your skin. If you are trying to lose weight perhaps it is worth trying as a complement to a healthier diet and or moderation. Other options for omega 3 are flaxseed oil in capsules, fish oil or to eat salmon.