Nutrition: Sweet Potato (A Paleo Exception) - Explore Fitness

The sweet potato is a moderate GI (glycaemic index) carbohydrate and is very high in Vitamin A (a fat-soluble antioxidant).  Vitamin A (beta-carotene) is what gives sweet potatoes the rich orange colour (some sweet potatoes are purple in colour).
To maximise absorption of vitamin A ensure you have adequate fat with your meal to ensure the body is better able to utilise this antioxidant.
Interestingly a study several years ago of 10,000 Finnish smokers found that those with higher levels of Vitamin A (beta-carotene) in the blood had a lower incidence of lung cancer.  This was only the case with Vitamin A from natural sources though, not that coming from synthetic vitamin supplementation where lung cancer rates where actually found to be higher! [1]  Another reason to stick to natural sources for antioxidants!
In Loren Cordain's book "Paleo Diet For Athletes" the sweet potato is also considered as one of the better options for recovery from extended endurance work.  This book goes into great detail of nutrition for pre-, during and post-activity.
The sweet potato also includes Vitamin C, E, B6 - the micronutrients manganese, copper and traces of potassium and iron.  Anthocyanin is a colour related pigment which studies have shown to have anti-inflammatory properties another property supporting one's recovery from activity.[2]
Here's a recipe for Sweet Potato Chips (using coconut oil for adequate fat intake).

via thefitnessexplorer.com

Excellent alternative to potatoes, especially if you are avoiding the deadly nightshade family because of joint pain.