
It's why the study is being greeted with a lot of excitement. For instance, see this NPR story on the research -- which is where the picture comes from. Here's a link to the study.
The results showed a big difference in triglyceride and insulin levels (although not in blood glucose levels). The same men had 31% lower TG levels and 21% lower insulin levels after eating the experimental meal, which was made of the same basic food but with the addition of 14 grams of spices, compared to what their levels were after the control meal.
There are a lot of reasons for caution: the sample size was small, the subjects were overweight but otherwise healthy (so they had for example normal insulin responses to blood glucose, unlike many who have diabetes or insulin resistance), and they used a mix of spices so it's hard to know which spice(s) were the ones that helped prevent absorption of fats into the blood and kept insulin levels from rising too high. Also, 14 grams of spices in a single meal seems excessive, although the subjects had no bad reactions from eating this much spice.
Here's the good news and take away: this study and others like it reinforce a truth discovered by Ayurvedic practitioners centures ago: spices help keep us healthy! Here, we see that eating a fairly large combination of spices as part of our meal, as is typical of a healthy Indian diet, can help keep us healthy even if the meal is full of carbs and fat.
Thanks to my brother for the tip.