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Avocados Help Lower Cholesterol

Avocados are the perfect example of how delicious healthy eating can be! Researchers assigned 45 overweight and obese adults to one of three cholesterol lowering diets: a lower fat (24% calories from fat) diet, a moderate fat (34% calories from fat) diet with one avocado per day, and a moderate fat (34% calories from fat) diet with sunflower and canola oils. Those on the avocado diet lowered their “bad cholesterol” significantly more than those on the other diets. Additionally, the avocado group was the only group to significantly decrease LDL particle number (a risk factor for heart disease) and improve the ratio of LDL to HDL (the gap between “bad” and “good” cholesterol). 
Journal of the American Heart Association. 2015 Jan 7 (Wang L et al.).

An Avocado a Day May Keep High Cholesterol Away

Replacing saturated fats (like butter and red meat) with unsaturated fats (like nuts, seeds, olive oil, and avocados) as part of an overall healthy diet is thought to be an effective strategy to help prevent heart disease. To see if people’s cholesterol levels and heart disease risk would decrease by substituting some of the saturated fat in their diets with healthier monounsaturated fats from oils or avocados, scientists randomly assigned 45 overweight and obese adults to 1 of 3 cholesterol lowering diets (one low fat, one moderate fat with sunflower oil, one moderate fat with avocados). They found that replacing saturated fat with monounsaturated fats did indeed have a positive effect on cholesterol and heart disease risk, but that the best improvement was seen in people who ate 1 avocado per day, compared to the group who ate extra oil. The avocado group even saw improvements in small dense LDL, the type of cholesterol thought to be most dangerous.
Journal of the American Heart Association. 2015 January; 4: e001355. (Wang L et al.) 

Wild Ferns are an Important Part of Sub-Saharan African Diet

Pteridophytes, also known as ferns or fern allies, may sound exotic to people in the USA, but in Africa they are a crucial source of food. Many rural communities in sub–Saharan Africa depend on these wild edible plants not only during times of food shortage, but also as a pivotal component of their normal diets. There are at least 24 different species of pteridophytes eaten, with Pteridium aquilinum being the most widely consumed. These ferns also pack a punch when it comes to nutrition, with higher levels of minerals, carbohydrate, and protein than other common vegetables. There remains much to learn regarding the role of ferns in the sub–Saharan African diet and culture.
Journal of Ethnobiology and Ethnomedicine. 2014 Dec; 10: doi: 10.1186/1746–4269–10–78. (Maroyi A.)

Healthy Diet with Whole Grains, Fruits, Vegetables, and Dairy Contains Friendly Microbes

Microbes are important for our digestive health, and researchers still have much to learn about how different foods impact our gut microbiome. In this study, researchers cooked 3 days worth of food from 3 different diets (a typical American diet with lots of convenience foods; a USDA recommended healthy diet with whole grains, fruits, vegetables, dairy, and lean meats; and a vegan diet consisting only of plant foods) and then analyzed the microbes present in the foods. The USDA recommended healthy diet was shown to have the highest total microorganisms. However, it was also the only meal plan that included yogurt, a non-heat-treated fermented food well known for its probiotic content.
PeerJ. 2014 Dec 9;(2):e659. doi:10.7717/peerj.659 (Lang JM et al.)

Short Term Benefits of Plant-Based Diets on Nutrient Intake and Inflammation

In a study of 63 overweight and obese adults instructed on various diets, South Carolina researchers examined the differences in nutrient intake and Dietary Inflammatory Index (DII). After two months, those assigned to vegan, vegetarian, and pescatarian diets had significantly lower DII scores and greater improvements in fiber, carbohydrate, fat, saturated fat, and cholesterol. However, after six months, no differences were seen among the diets. Due to these short-term benefits, the researchers concluded that greater consideration should be given to “finding ways to provide support for adoption and maintenance of plant-based dietary approaches.”
Nutrition Research. 2014 Dec 3. Pii:S0271-5317(14)00267-X. (Turner-McGrievy GM et al.)

Mediterranean Diet Associated With Healthy Aging, DNA

Telomeres, DNA sequences at the end of chromosomes, can tell us a lot about aging and longevity, as shorter telomeres are associated with many age related diseases, such as heart disease and cancer. To determine the relationship between DNA and diet, Harvard researchers analyzed food intake and telomere length from over 4,600 healthy nurses using data from the Nurses’ Health Study. Researchers found that people with the greatest adherence to the Mediterranean Diet (lots of vegetables, fruits, grains (mostly unrefined), fish, legumes, and nuts, and less meat) had the longest telomeres, a good indicator of healthy aging. Additionally, the scientists pointed out that no one specific food was pinpointed as the best, reinforcing the importance of a well-rounded, healthy diet.
British Medical Journal. 2014 Dec 2;349. (Crous-Bou M et al.)

Olive Oil May Decrease Risk for Coronary Artery Disease

The Mediterranean Diet has long been associated with a reduced risk of heart disease, so researchers decided to take a closer look at how olive oil, one of the staples of this cuisine, might play a role in heart health. In a European study, researchers gave 63 healthy participants a daily 20 ml supplement of either refined olive oil (low phenolic content) or extra virgin olive oil (high phenolic content) for six weeks. Then researchers measured the participants for urinary proteomic biomarkers (certain peptides in the urine that are associated with specific diseases). After the six-week supplementation, both olive oil groups showed a significant improvement in the biomarkers for coronary artery disease, but no significant difference in the biomarkers for diabetes or chronic kidney disease, and no significant change in cholesterol levels.
American Journal of Clinical Nutrition. 2014 Nov 19 [Epub ahead of print] (Silva S et al.)

Vegetable Intake Linked with Less Fatty Liver, Better Insulin Resistance

To see how vegetable intake relates to adolescent metabolic health, researchers analyzed the eating patterns and health outcomes of 175 overweight Latino youth (average age = 15) in California over 5 years. Teens who ate 2.5 servings of vegetables per day (excluding fried vegetables) had 39% less fat in the liver (measured by HFF) compared with those who hardly ate any (0.1 servings per day), with even stronger results for non-starchy vegetables, especially dark green and orange vegetables. Those who ate the most non-starchy vegetables (1.7 servings per day) also had significantly better insulin resistance, and 54% less prevalence of non-alcoholic fatty liver disease than those who ate the least (0.1 servings per day). The difference in dark green and orange vegetable consumption between the highest and lowest groups was just ½ serving (or ¼ cup), meaning that a small scoop of carrots or broccoli could potentially go a long way towards health.
Journal of the Academy of Nutrition and Dietetics. 2014 Nov;114(11):1776-83. (Cook LT et al.)

Mediterranean Diet May Protect Against Inflammatory Diseases

Chronic inflammation (the body’s response to stress) is linked with a number of diseases. To see how diet may play a role, Spanish researchers reviewed data on the Mediterranean diet and inflammatory disease, and found that following a Mediterranean diet is linked with both short and long term benefits for inflammatory diseases. In the short term, Mediterranean diets can help reduce risk factors associated with cardiovascular disease, like blood pressure and cholesterol. But the benefits of following a Med diet persist over time. In the long term, following this eating pattern has an intense, systemic, anti−inflammatory effect. This suggests that adherence to a Mediterranean diet may help protect against diseases like atherosclerosis, cancer, and neurodegenerative diseases, such as Alzheimers disease.
Endocrine, Metabolic & Immune Disorders−Drug Targets. 2014 Nov;14:245−254. (Casas R et al.)

Med Diet May Slow Decline in Kidney Function

Our kidneys have many important functions; besides filtering waste, they help control blood pressure, help make red blood cells, and more. The eGFR (estimated glomular filtration rate) is a blood lab that is used to assess kidney function, as low eGFR levels can indicate kidney damage or even kidney failure. In a 15 year study following  900 adults (free of stroke and coronary artery disease), researchers analyzed diet and eGFR status. The researchers found that people most closely following the Mediterranean Diet were least likely to have a low eGFR, and least likely to have a high rate of eGFR decline (which would have indicated a worsening of kidney function).
Clinical Journal of the American Society of Nephrology. 2014 Nov 7;9(11). (Khatri M et al.)

Vegetarian Diet Helps Diabetics Control Blood Sugar

Think a meat-centric diet is the best way to keep your blood sugar in check? Think again! Researchers in the United States and Japan reviewed studies that investigated the relationship between vegetarian diets and blood sugar control in people with type two diabetes. Analyzing data from the 255 adults included in the studies, scientists reported that a plant-based vegetarian diet helps adults with type 2 diabetes improve glycemic control, lower cholesterol intake by 173mg, and trim about 140 calories from their diets each day.  
Cardiovascular Diagnosis and Therapy. 2014 Oct;4(5):373-382. (Yokoyama et al.)

Mediterranean Diet Can Reverse Metabolic Syndrome

Metabolic syndrome is a dangerous cluster of 3 or more conditions: central obesity (storing fat around your middle), high blood pressure, high triglycerides (a type of fat in your blood), high LDL (bad) cholesterol, low HDL (good) cholesterol, and high blood sugar. Metabolic syndrome greatly increases your risk for heart disease and diabetes, but luckily, researchers found a delicious way to reverse the condition. Scientists in Spain reviewed data collected during the PREDIMED study in which over 7,400 adults at risk of heart disease were randomly assigned to eat 1 of 3 diets: Mediterranean Diet supplemented with extra-virgin olive oil, Mediterranean Diet supplemented with nuts, or a control diet (patients received advice on a low-fat diet). Researchers found that while the Mediterranean diet was not associated with the onset of metabolic syndrome, reversal of the condition (decrease in central obesity and/or high blood sugar) occurred in nearly one third of patients eating either version of the delicious and nutritious Mediterranean diet.
Canadian Medical Association Journal. 2014 Oct 14. Pii:cmaj.140764. [Epub ahead of print] (Babio N et al).

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