SHR

Adding fats to carbohydrate-containing meals is a common recommendation in dietetics to make meals “healthier” by reducing the glycemic response to the meal. The primary mechanism through which fat does this is by slowing the rate of gastric emptying, which leads to a slower appearance of glucose into the blood. Given that postprandial glycemia is an important risk factor for many diabetic complications, it makes complete sense to want to minimize post-meal blood glucose excursions. However, to focus solely on the blood glucose response of a meal misses the forest for the trees. There is a considerable amount of evidence to suggest that consuming starchy carbohydrates in combination with excessive dietary fat, especially saturated fat, causes an acute state of insulin resistance that may last for hours after the meal. This has been known since at least 1983, when Collier and O’Dea published research showing that adding butter to a potato...

Iron and metabolic syndrome; a shield for women and sword for men In an analysis of 3,271 Swiss men and women, Kilani et al found a significant relationship between serum transferrin levels and increased risk of metabolic syndrome (MetS) in men only, whereas serum iron was found to be significantly protective against MetS in women. Ferritin showed no associations with either sex. Although causality cannot be determined, two mechanisms have been proposed. The first is that MetS leads to increased inflammatory status that leads to changes in iron homeostasis. The second is that elevated transferrin leads to MetS through a complex web of mechanisms beginning with excessive formation of reactive oxygen species and ending with insulin resistance and related comorbidities. It’s the little things MicroRNAs (miRNAs) are small noncoding RNAs that have the ability to control multiple genes and govern remote bodily processes through intertwined pathways. Researchers from the University of...

Dairy fat is a complicated topic because it is typically around 70% saturated fat but shows very inconsistent effects on blood lipids and cardiovascular disease (CVD) risk. However, if we narrow things down farther from dairy fat and focus on the foods which contain it, there is a lot of evidence from randomized controlled trials that diets high in saturated fat derived largely from butter fat increases LDL-c, whereas cheese intake results in lower LDL-c compared with butter of equal fat content. However, every trial showing these effects has used very high amounts of butter. For instance, one study replaced 13% of the subject’s caloric intake with butter, which corresponded to an average of 50 grams (almost one-half of a stick) of butter per day. In order to evaluate the effects of moderate butter consumption on CVD risk factors, Engel and Tholstrup from the University of Copenhagen, Denmark recruited 47 healthy...

It was recently reported by an updated Cochrane Review that reducing saturated fat intake lowered the risk of having a heart attack without affecting the risk of dying from one. These effects were most pronounced when the saturated fat (SFA) was replaced by linoleic acid (PUFA), but there was surprisingly no observable benefit of replacement with monounsaturated fats (MUFA). However, the trials included in this meta-analysis were primarily interventions where only dietary advice was given to the participants who were then followed for some time, and the majority of participants were those who were at a high-risk of cardiovascular disease (CVD) and/or already had a heart attack. Thankfully, researchers from the University of Reading, UK recently published findings from the DIVAS study that should help shed some light on the issue of fat quality and CVD. The DIVAS study was a 16-week 195-person intervention in which the participants were randomized to...

Eating more veggies doesn’t help those at risk for heart attacks. It is probably one of the most ubiquitous nutrition recommendations in existence – eat more vegetables. Only recently have researchers from Ireland actually put this to the test in overweight-obese men and women. All 89 of the participants were habitual low-veggie consumers with no outstanding medical history other than a blood lipid panel that put them at a high risk for heart disease. Over a 4-week run-in period, all participants consumed <2 servings of vegetables per day (1 serving = 80g), after which they were randomly allocated to consume 2, 4, or 7 portions per day for the following 12 weeks. There were literally no changes in any outcome, including body composition, blood lipids, blood pressure, or C-reactive protein. Reducing saturated fat consumption may reduce the risk of having a heart attack, but it won’t protect you from dying from...