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 it.

The Cochrane Database just released their most recent review and meta-analysis of all published randomized clinical trials assessing the effect of reducing and/or replacing dietary saturated fat (SFA) on cardiovascular morbidity and mortality. Overall, 15 studies with over 59,000 participants were included and the analysis concluded that there was no clear benefit of reducing and/or replacing SFA on all-cause and cardiovascular mortality. However, reducing SFA led to a 17% reduction in the risk of having a heart attack or stroke, and replacing SFA with polyunsaturated oils reduced the risk by 27%. These protective effects were mediated entirely by reductions in blood cholesterol levels, as studies in which cholesterol was unchanged showed no benefit. Replacing SFA with monounsaturated fats, carbohydrates, or protein also had no benefit.

Vitamin C doesn’t help manage blood lipid levels PLUS for everyone who still thinks that synthetic and food-derived vitamin C are different – they aren’t.

As if vegetables and fruits don’t provide enough, vitamin C is probaly one of the most common supplements that people take. Although reasons for supplementation vary greatly, Ammar Ashor and colleagues from Newcastle University were interested in its effects on blood lipids. They conducted a systematic review and meta-analysis of 40 randomized clinical trials including over 1900 men and women ranging from 20-81 years of age. Overall, vitamin C supplementation had no significant effect on lipid profile, and the significant findings in sub-group analyses were clinically worthless. For instance, a significant HDL-c raising effect was found in type-2 diabetics that amounted to 2 mg/dL. The two subgroups that benefited were those with greater risk of cardiovascular diseases and those who had low baseline vitmain C levels.

While we’re on the topic of vitmain C, it is worth mentioning that complete bioavailability of oral supplementation is achieved with 200 mg while bioavalability is reduced to 33% with a 1250 mg dose in healthy persons. In other words, 1250 mg is effectively 400 mg and it may be prudent to supplement with lower doses of around 200 mg more frequently throughout the day. Also, for everyone who still thinks that synthetic and food-derived vitamin C are different – they aren’t, they are chemically identical, and although foods are rich in numerous micronutrients and phytochemicals that may affect the bioavailability of vitamin C, they don’t. If anything foods are probably worse, as one study documented an increased excretion rate with no difference in absorption of vitmain C in subjects who ate golden kiwis compared to subjects who chewed an ascorbic acid tablet.

Almonds – great for the diet but not for the heart

Nuts in general have long been regarded as heart-healthy because of their fatty acid and micronutrient profile. Whether this is true for almonds was recently put to the test by researchers from the USDA Human Nutrition Research Center on Aging at Tufts University. They recruited 45 elderly & overweight-obese men and women with diagnoses coronary artery disease to consume for six weeks in a randomized cross-over design either 85g (3 oz.) of almonds per day or nothing at all. Consuming almonds significantly increased the dietary intake of vitamin E, riboflavin, choline, calcium, copper, potassium, magnesium, manganese, phosphate, and zinc, as well as total calorie and protein intake (each by 30%!). And all that is great, but there was no effect on blood pressure, flow-mediated vasodilation, blood lipids, or inflammatory markers. Nonetheless, all subjects were treated with multiple medications during the trial that may have masked an impact of the almond intervention.