A Recipe for Success: The University of Arkansas Division of Agriculture - Color Variation in Poultry Meat

There are two types of meat light and dark also called white and red respectively. The dark meat has a higher concentration of myoglobin. There are a few other differences in the muscles, such as dark muscle is the muscle of sustained contracting ability, the slow muscle.
Light or white muscle is the muscle of quick action, the fast muscle.

Birds such as ducks and geese which fly long distances have dark meat. Fast flying birds such as quail have light colored meat. A duck is a long distance flyer, a quail flies in a short quick burst of speed. Both of the meat colors are low in fat compared to other types, such as red meat from cattle. However, the white meat is lower fat than the dark poultry meat. If the skin is removed then white meat is very low fat.

4. Is light poultry meat healthier than dark meat? 

The question of healthier sort of depends. White meat is a little lower in fat content than dark. But white meat is lower in myoglobin than dark meat. If you needed the fat, then you might consider it more healthy from a need standpoint or vice versa. The same would hold true for the myoglobin, if you needed less in your diet then white meat would be better than dark.

5. Are there conflicting theories to whether one meat is healthier than the other?

This question is really answered above and is sort of a “it depends” type of question. If you need less fat, white meat is a little lower than dark. If you need more myoglobin then dark has more than white. You can see how the question could be answered either way depending on your need and/or perspective.

6. What further research needs to be done in this area, if any?

There is always a need for research. Muscle contains many things other than fat and myoglobin. For example, minerals and vitamins.