Don't take my word for it, just peep the Wikipedia excerpt below and decide for yourself:
(Wikipedia) "In order to achieve profit, the owners of the ships divided their hulls into holds with little headroom, so they could transport as many slaves as possible. Unhygienic conditions, dehydration, dysentery and scurvy led to a high mortality rate, on average 15% and up to a third of captives.
Often the ships, also known as Guineamen, transported hundreds of slaves, who were chained tightly to plank beds. For example, the slave ship Henrietta Marie carried about 200 slaves on the long Middle Passage. They were confined to cargo holds with each slave chained with little room to move."
So, you may want to think twice before you take that next planking photo.