A 2016 study linked the removal of artificial trans fat from the food supply to a decreased incidence of cardiovascular-related events, specifically heart attack and stroke. Researchers conducted a retrospective observational pre-post study looking specifically at populations impacted by the trans fat restrictions imposed in New York state between 2007 and 2011. Highly urban counties with trans fat restrictions (11 counties, n = 8.4 million) were compared to highly urban counties with no restrictions (25 counties, n = 3.3 million). Results showed that three or more years after the regulation was implemented, there was a 6.2 percent decline, beyond background temporal trends, in hospital admissions for heart attacks and stroke events combined in counties that banned trans fats compared with those that did not. Heart attacks were significantly reduced by 7.8%, while strokes showed a non-significant reduction of 3.6%.
Cornell researchers explored the economic impact of replacing 5% of energy from dietary saturated fats with equivalent energy from monounsaturated fats.
The 2016 study, published in the Journal of Medical Economics, analyzed data from 247,700 adults from the 2000–2010 Medical Expenditure Panel Survey to estimate cost savings from avoided heart disease. Savings associated with reduced absenteeism from avoided heart disease was estimated from 164,577 adult responses from the survey. Results showed this dietary switch could save the U.S. $25.7 billion in heart-disease related healthcare costs annually, with savings realized by multiple payers including private insurance, Medicare and Medicaid, and patients. Beyond direct healthcare costs, results also estimated up to $1.2 billion in productivity could be saved each year from fewer days of work lost due to heart disease.
Research published in the Journal of the American Medical Association linked specific dietary factors to cardiometabolic mortality, including heart disease, stroke and type 2 diabetes.
Study authors compared NHANES data from 1999–2002 and 2009–2012 to assess associations between specific dietary factors and cardiometabolic-related mortalities. Results showed nearly half (45.4%) of the 702,308 cardiometabolic deaths in 2012 were associated with suboptimal intakes of specific foods and nutrients. Excessive sodium intake was the leading contributor (9.5% of deaths), followed by low consumption of nuts and seeds (8.5%), high processed meat intake (8.2%) and low consumption of omega-3 fats (7.8%).
Researchers also noted an improvement on many of the dietary contributors during the 10-year span, resulting in a 26.5% reduction in cardiometabolic-related deaths. This was tied most significantly to increased consumption of polyunsaturated fat intake, but other factors included increase intake of nuts and seeds, drop in sugar-sweetened beverage intake and rise in unprocessed red meat intake.
Results from a 2016 study evaluated the association between dairy fat and cardiovascular risk and estimated how this impact could be altered based on replacement with PUFA or vegetable fat.
Subjects included 222,234 individuals in the Health Professionals Follow-Up Study and Nurses’ Health Studies. Food frequency questionnaires, deployed every four years, assessed dietary fat intake from dairy and other fat sources. When compared with equivalent amounts of energy derived from carbohydrates, dairy fat intake did not increase cardiovascular risk, coronary heart disease or stroke. However, when 5% of energy from dairy fat was replaced with an equal energy amount from polyunsaturated fat or vegetable-based fat, cardiovascular risk decreased by 24% and 10%, respectively. Substituting other animal fat for dairy fat was associated with a 6% increase in cardiovascular risk, coronary heart disease and stroke.
Research published in the New England Journal of Medicine suggests that following a Mediterranean diet that includes extra-virgin olive oil and mixed nuts may also help reduce the risk of cardiovascular events. Subjects were 7,447 people between the ages of 55 and 80 who were at high cardiovascular risk and were randomized to follow either a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts or a low-fat control diet. The results showed both Mediterranean diets can lead to an approximately 30% percent relative risk reduction for major cardiovascular events. The data also show a significant risk reduction for stroke in the Mediterranean diet groups.
A 2017 observational study shows improvements in cholesterol and triglyceride levels may be contributing to the decline in cardiovascular-related death rates.
Authors analyzed eight 2-year National Health and Nutrition Examination Survey cross-sectional cycles between 1999/2000 and 2013/2014 among adults ages 20 years and older. There were 39,049 adults who had total cholesterol levels analyzed, 17,486 who had triglyceride levels analyzed and 17,096 who had triglyceride levels and LDL cholesterol levels analyzed. Between 1999/2000 and 2013/2014, the average age-adjusted total cholesterol decreased by 15 mg/dL, age-adjusted average triglyceride levels decreased by 26 mg/dL in 2013/2014, and average LDL cholesterol decreased by 15 mg/dL. Authors suggest the removal of trans fats from food is a possible explanation for the reductions.
An analysis published in the Annals of Internal Medicine found a Mediterranean diet reduced the risk of type 2 diabetes, heart disease and breast cancer.
Researchers reviewed data from 53 studies that examined the health effects of the Mediterranean diet. The studies were controlled trials of 100 or more persons who were followed for at least one year. Cohort studies for cancer outcomes also were included. The analysis found that people who followed a Mediterranean diet reduced the risk of type 2 diabetes by 30%, had a 29% lower risk of heart disease and a 57% reduced risk of breast cancer. No apparent effects on all-cause mortality were observed. Researchers highlighted the need for more research on the relationship between breast cancer and the Mediterranean Diet, since only one randomized trial involving breast cancer was included in the analysis.
New parents may be at higher risk for chronic disease, a recent study shows. According to a study published in the Journal of the Academy of Nutrition and Dietetics, new parents tend to eat more saturated fat than people who aren’t parents, placing them at higher risk for developing obesity, high cholesterol, heart disease, and Type 2 Diabetes. The lead author cites convenience foods as the primary culprit, due to the time constraints and stress of parenthood. Overall, diets of parents and non-parents remained fairly similar throughout the seven-year study, with the exception of saturated fat.
Results from a meta-analysis show eicosapentaenoic and docosahexaenoic acids (EPA + DHA) are as effective, if not more effective in some cases, as lifestyle interventions for reducing blood pressure in non-hospitalized patients who are hypertensive but not currently taking any blood pressure medications.
The study included 70 randomized controlled trials that examined the effect of EPA + DHA on both systolic and diastolic blood pressure. In all studies, compared with placebo, EPA + DHA intake was associated with significantly greater reductions in both blood pressure measurements. Seafood, fortified foods, fish and algal oil, as well as purified ethyl esters, were the most common sources of the fatty acids. Study authors stated these results are statistically significant, as well as clinically meaningful, and indicated that EPA + DHA could prevent an individual from needing to take antihypertensive medication and could help those in a lower stage of progressive hypertension control their blood pressure.
A research study found supplementation of cis-palmitoleic acid, a naturally occurring omega-7 monounsaturated fatty acid, benefited heart health by producing reductions in C-reactive protein, triglycerides, and LDL cholesterol, along with an increase in HDL cholesterol.
In this double-blind, randomized controlled trial, 60 adults with dyslipidemia and elevated C-reactive protein were split into two groups. One group took a daily supplement of purified cis-palmitoleic acid for 30 days while the other group took a placebo. All subjects were instructed not to change their current diet during the study. Compared to the control group, the supplement group experienced a 44% reduction in C-reactive protein, 15% reduction in trigylcerides, an 8% decrease in LDL, and a 5% increase in HDL.
A study published in Stroke found that high adherence to a Mediterranean diet was associated with a reduced incidence of ischemic stroke.
In this cohort study, 20,197 subjects age 45 and older were evaluated on their adherence to a Mediterranean diet. Participants received scores from 0-9, based on their adherence. Over the course of the follow up (an average 6.5 years), 565 participants had strokes (88% ischemic, 12% hemorrhagic). After adjusting for uncontrolled variables, researchers found a 21% reduced risk for ischemic stroke when comparing high (5-9) and low (0-4) adherence to the Mediterranean diet. When groups were split into high (6-9), moderate (4-5) and low (0-3) categories, risk reduction ranged from 22% to 31%. In addition, for every 1-point increase in score, there was a 5% reduction in risk. No relationship was found between adherence and risk for hemorrhagic stroke.
An increased intake of monounsaturated fats (MUFAs, such as canola or sunflower oils) may raise HDL cholesterol (i.e. good cholesterol) without raising LDL cholesterol (i.e. bad cholesterol). Researchers with the Clinical Nutrition and Risk Factor Modification Centre at St. Michael’s Hospital in Toronto recruited patients with hypercholesterolemia (presence of high levels of cholesterol in the blood) and provided a restricted diet high in MUFAs, which included high-MUFA sunflower oil. After two months, the researchers noted the addition of MUFAs increased HDL cholesterol in patients consuming the specialized diet. Researchers concluded that cholesterol-lowering diets may be ‘significantly’ enhanced if dieters include a moderate amount of monounsaturated fat.
Monounsaturated fats (omega-9 fatty acids) have been shown to decrease LDL ‘bad’ cholesterol while also having positive effects on HDL (‘good’) cholesterol and total cholesterol levels. Researchers at the University of Manitoba compared a diet rich in high-oleic canola oil versus a typical western diet (high in saturated fat). Participants who consumed the diet high in omega-9 fatty acid demonstrated lower total cholesterol levels, including a 7% reduction in LDL cholesterol. The authors concluded that consumption of the high-oleic canola oil was cardioprotective.
In a recent article from Circulation, dietary linoleic acid was shown to reduce the risk of heart disease when replacing saturated fat.
In this meta-analysis of prospective cohort studies, researchers focused on dietary linoleic acid, the predominant fatty acid in polyunsaturated fat. Researchers evaluated all recent studies that reported an association between omega-6 fatty acids and coronary heart disease. Final data included more than 310,000 subjects, representing 13 published and unpublished cohort studies. Results showed that for each 5% energy increase of omega-6 that replaced equivalent energy from saturated fat, there was a 9% lower risk of cardiovascular events and a 13% lower risk of coronary heart disease deaths. These data confirm that when polyunsaturated fat replaces saturated fat, the risk for cardiovascular disease decreases.
Research examining more than one hundred participants at risk for metabolic syndrome shows canola and high-oleic canola oils can lower abdominal fat when used in place of other selected oil blends in a diet for weight maintenance.
Presented at the American Heart Association’s EPI/NPAM 2013 meeting, the study indicates participants were given a calorie-controlled, heart-healthy diet with a daily smoothie containing one of five study oils. Results showed that consuming canola or high-oleic canola oils on a daily basis for four weeks lowered belly fat by 1.6%. Abdominal fat was unchanged by the other three oils, which included a flax/safflower oil blend, corn/safflower oil blend and high-oleic canola oil enriched with DHA. The data indicates that simple dietary changes, such as using a high monounsaturated fat vegetable oil, may reduce the risk of metabolic syndrome and therefore, heart disease, stroke and type 2 diabetes.
Research from Circulation found that linoleic acid, the major dietary n-6 polyunsaturated fat, may lower risk of total and coronary heart disease mortality in older adults.
In this prospective cohort study, 2,792 subjects without cardiovascular disease were evaluated for total and cause-specific mortality between 1989 and 2010. Analyses included evaluations of linoleic acid, γ-linolenic acid, dihomo-γ-linolenic acid and arachidonic acid. The results demonstrated that higher linoleic acid levels were associated with a 13% lower total mortality. Other circulating n-6 fatty acids, including arachidonic acid, were not significantly associated with total or cardiovascular disease mortality.
Results from a 2015 study show consuming tree nuts may lead to better adiposity measures and cardiovascular and metabolic syndrome health risk factors. Researchers used NHANES 2005–2010 data to examine the relationship between tree nut consumption and health risks in 14,386 adults. Tree nuts included almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts. Results showed that consuming at least ¼ ounce of tree nuts per day was associated with lower BMI, waist circumference, systolic blood pressure, insulin resistance and higher HDL cholesterol, compared with no consumption.