It depends on what your definition of "healthier" is and what your goals are. Traditionally, goat's milk has been a "convenience" option for all babies requiring formula, including humans. My father used to raise a nanny goat as a child in 1920's Savannah, Georgia to sell milk to women who needed extra milk for their babies. Goat milk is good for this because the fat molecules are so small that the milk is naturally homogeneous.

I am only referring to whole milk because goat's milk is not typically separated and reconstituted into different products like cow's milk. Yes - yes - the milk in the store is first separated and then remixed to skim, 1% and 2%. It comes from a variety of animals. Store-bought goat's milk is the same, but not as cost-effective since it doesn't separate easily (butter is white). Basically it has to be centrifuged. Additionally, because batches are not produced on the same scale, milk comes from fewer animals, often from the same or fewer herds.

For the average adult, the protein and calcium richness may be nutritionally similar to milk. Goat milk is slightly higher in macronutrients and slightly lower in sugars. Because it has lower lactose content, it is better tolerated by people with lactose intolerance. Vitamin D is commonly added to two commercial products. Goat milk is more susceptible to spoilage. As it ages, it becomes "goatskin". I have never tasted fresh commercial goat milk like I did.

The real factor for me personally is the source of the milk. When I drink milk, I like to buy it from a local dairy that has all the herds in Jersey and sells cream line milk. Most people can find this milk at Whole Foods or their local grocery store. We drink goat's milk from our own herd as a seasonal product from April to September (I love resting my girls in the winter). Goat milk and cow's milk, which come from different breeds of livestock, have different nutritional profiles, especially in terms of lipid (fat) content. I just like the taste of Jersey milk, not Holstein milk. Holsteins are these huge black and white cows that are the source of most of the milk in the United States.