Fears of high cholesterol were frequently voiced up until the mid-1990s. However, more recent research has shown that the distinction between high- and low-density lipoprotein ('good' and 'bad' cholesterol, respectively) must be addressed when speaking of the potential ill effects of cholesterol. Different types of dietary fat have different effects on blood levels of cholesterol. For example, polyunsaturated fats tend to decrease both types of cholesterol; monounsaturated fats tend to lower LDL and raise HDL; saturated fats tend to either raise HDL, or raise both HDL and LDL; and trans fat tend to raise LDL and lower HDL.
^ Jump up to: a b Vos, Miriam B.; Kaar, Jill L.; Welsh, Jean A.; Van Horn, Linda V.; Feig, Daniel I.; Anderson, Cheryl A.M.; Patel, Mahesh J.; Cruz Munos, Jessica; Krebs, Nancy F.; Xanthakos, Stavra A.; Johnson, Rachel K. (22 August 2016). "Added Sugars and Cardiovascular Disease Risk in Children". Circulation. 135 (19): e1017–e1034. doi:10.1161/CIR.0000000000000439. PMC 5365373. PMID 27550974.
Stephen Colbert may be on to something. UCLA Center for Human Nutrition researchers divided study participants into two groups, each of which were fed a nearly identical low-cal diet for 12-weeks. The only difference between the groups was what they were given to eat as an afternoon snack. One group ate 220-calories of pretzels while the other group munched on 240-calories worth of pistachios. Just four weeks into the study, the pistachio group had reduced their BMI by a point, while the pretzel-eating group stayed the same, and their cholesterol and triglyceride levels showed improvements as well.
Sure, nuts aren’t known for being low in calories, but they have an array of other properties—namely a high protein and fiber content—that makes them ideal for weight loss. A study published in the Journal of the American Heart Association, Circulation, found that consuming 1.5 ounces of almonds daily (as opposed to a carb-dense muffin) along with a heart-healthy diet, helped to improve cholesterol and lipid profiles among the research participants. The study also found that eating almonds reduces belly fat, too.