Suffering from obesity or trying to lose weight? It might be time to add avocados to your daily diet. A recent study suggests that meals which include fresh avocado can significantly suppress hunger.

 

Researchers at the Centre for Nutrition Research at Illinois Institute of Technology (USA) have found that substituting fresh avocado for refined carbohydrates can suppress hunger and increase meal satisfaction in overweight and obese adults. The findings of this study have been published in the scientific journal Nutrients.

 

Avocados are green, pear-shaped fruits of the avocado tree and are often categorised as a super-food. There have been numerous studies have shown that eating an avocado can improve heart disease risk factors like total ‘bad’ low-density lipoprotein (LDL) and ‘good’ high-density lipoprotein (HDL) cholesterol, as well as blood triglycerides.

 

The study had a total of 39 participants (21 men and 18 women) between the ages of 20 years and 65 years and a body mass index (BMI) between 25 and 35 with elevated fasting glucose and insulin concentrations. Participants were also non-smokers and in relatively good health with no previous history or current clinical evidence of cardiovascular, metabolic, respiratory, renal, gastrointestinal or hepatic diseases. The goal was to assess the underlying physiological effects of including whole and half fresh Hass avocados on hunger, fullness and how satisfied subjects felt over a six-hour period. Researchers evaluated these effects in the participating overweight and obese adults with a randomised three-arm crossover clinical trial. 

 

The participants had three breakfast test meals—one was a low fat, high carbohydrate meal (the control meal) and two meals were similar in energy and energy density to the control but contained either half or whole of a fresh medium-sized Hass avocado. Meals consisted of a bagel sandwich (with or without avocado), fresh honeydew melon, oatmeal and a lemonade flavoured drink. 

 

Avocado derived fat and fibre increased with increasing avocado content in the meal, with whole avocados containing more than two thirds of avocado derived fat and fibre. A meal containing half an avocado was supplemented with butter fat to adjust total fat content between the two experimental avocado meals. Bagel sandwiches were used for manipulating components by adding avocado into hollowed bagels and using cream cheese and butter to manage desired fat levels and textural quality. Green leafy lettuce was also used in all bagel sandwiches to help mask substitutions and control for colour, visual appeal and texture. 

 

Participants came to the laboratory on three separate occasions and consumed each meal once, based on a randomly assigned sequence that was generated by a computer. Researchers found that 31 people, with a BMI over 30, found that the buttery fruit worked well as a replacement for processed carbs like bread and pasta, suppressing hunger and fuelling weight loss for hours. These dietary changes were also shown to limit insulin and blood glucose excursions, further reducing the risk of diabetes and cardiovascular disease by adding healthy fats and fibres into a regular daily diet. 

 

As rates of obesity continue to rise around the world, the findings from this research suggest that simple dietary changes can have an important impact on managing hunger and aiding metabolic control. “For years, fats have been targeted as the main cause of obesity, and now carbohydrates have come under scrutiny for their role in appetite regulation and weight control,” said Dr Britt Burton-Freeman, director of the center for nutrition research at Illinois Tech. “There is no ‘one size fits all’ solution when it comes to optimal meal composition for managing appetite. However, understanding relationship between food chemistry and its physiological effects in different populations can reveal opportunities for addressing appetite control and reducing rates of obesity, putting us a step closer to personalised dietary recommendations.”

We have already heard that consuming nuts is one of the key factors in improving brain health. Now, a new study has found that consuming walnuts is beneficial for people who are at risk of heart disease and helps them lower their blood pressure. 

 

The study was conducted by a research team from Penn State University led by Prof Penny Kris-Etherton and was published in Journal of the American Heart Association. Researchers reported that when participants’ combined a diet low in saturated fats with eating walnuts, it lowered blood pressure in people at risk of cardiovascular disease.  

 

For the study, the researchers examined effects of replacing some of the saturated fats in participants’ diets with walnuts, in a randomised and controlled trial. A total of 45 participants, who were either overweight or obese and between the ages of 30 and 65, were recruited. Before the study began, they were placed on a ‘run-in’ diet for a period of two weeks. “Putting everyone on the same diet for two weeks prior to the start of the study helped put everyone on the same starting plain,” said Dr Alyssa Tindall, one of the other researchers working in Prof. Kris-Etherton’s lab. This initial run-in diet included 12% of their calories from saturated fat, in order to mimic an average American diet. This way, when the participants started on the study diets, researchers could know with certainty that the walnuts or other oils had replaced saturated fats.

 

Dr Tindall said that the study was one of the first to try to uncover which parts of the walnuts help support heart health. “Walnuts contain alpha-linolenic acid - ALA - a plant-based omega-3 that may positively affect blood pressure,” she said. “We wanted to see if ALA was the major contributor to these heart-healthy benefits, or if it was other bioactive component of walnuts, like polyphenols. We designed the study to test if these components had additive benefits.”

 

After the run-in diet, participants were randomly assigned to one of three study diets, all of which included less saturated fat than the run-in diet. One of the study diets incorporated whole walnuts, another included the same amount of ALA and polyunsaturated fatty acids without walnuts, and the third diet had partially substituted oleic acid (another fatty acid) for the same amount of ALA found in walnuts, without any walnuts.

 

All three diets substituted walnuts or vegetable oils for 5% of the saturated fat content of the run-in diet, and all participants followed each diet for six weeks, with a break between diet periods. Following each diet period, the researchers assessed participants for several cardiovascular risk factors including central systolic and diastolic blood pressure, brachial pressure, cholesterol and arterial stiffness. 

 

They found that when participants ate whole walnuts daily in combination with lower overall amounts of saturated fat, they had lower central blood pressure—the pressure moving towards your heart. It provides information about a person’s risk of developing cardiovascular disease (CVD).

 

Since the study suggests that walnuts were the cause of lower central pressure, Prof Kris-Etherton believes that their risk of CVD may have also decreased. “When participants ate whole walnuts, they saw greater benefits than when they consumed a diet with a similar fatty acid profile as walnuts without eating the nut itself,” she explained. “So it seems like there’s a little something extra in walnuts that are beneficial -- maybe their bioactive compounds, maybe the fiber, maybe something else—that you don’t get in the fatty acids alone.” 

 

The research team was able to conclude that, while all treatment diets had a positive effect on cardiovascular outcomes, the diet with whole walnuts provided the greatest benefits, including lower central diastolic blood pressure. 

 

Dr Tindall said that the results underline the importance of replacing saturated fat with healthier alternatives. “An average American diet has about 12 percent calories from saturated fat and all our treatment diets all had about seven percent, using walnuts or vegetable oils as a replacement,” Dr Tindall said. “So, seeing the positive benefits from all three diets sends a message that regardless of whether you replace saturated fats with unsaturated fats from walnuts or vegetable oils, you should see cardiovascular benefits.”

 

Prof Kris-Etherton added that the study supports including walnuts as part of a heart-healthy diet. “Instead of reaching for fatty red meat or full-fat dairy products for a snack, consider having some skim milk and walnuts,” she said. “I think it boils down to how we can get the most out of the food we’re eating, specifically, how to get a little more bang out of your food buck. In that respect, walnuts are a good substitute for saturated fat.”

 

How well-meaning donations end up fueling an unproven, virtually unregulated $2 billion stem cell industry.

 

Their shoulders and backs and knees were giving out. Pills and steroid injections hadn’t eased their pain. They were scared of surgery. So, one afternoon last October, two dozen men and women, many of them white-haired, some leaning on canes, shuffled into a meeting room at Robson Ranch, a luxury retirement community in Denton, Texas. Sipping iced tea and clutching brochures that promised a pain-free tomorrow, they checked off their ailments on a questionnaire.

 

They were there to see a presentation by Dr. David Greene, who was introduced as a “retired orthopedic surgeon.” Atlas Medical Center, a local clinic that specializes in pain treatment, hosted the event. Greene, a short, trim man with his hair slicked up, ignored the stage and microphone and stood close to his audience. After warming up the crowd with a joke about his inept golf skills, Greene launched into his sales pitch. A tiny vial no larger than the palm of his hand, he told the group, contains roughly 10 million live stem cells, harvested from the placenta, amniotic fluid, umbilical cord or amnion, the membrane that surrounds the fetus in the womb.

 

Injected into a joint or spine, or delivered intravenously into the bloodstream, Greene told his listeners, those cells could ease whatever ailed them.

 

On a screen behind him, Greene displayed a densely printed slide with a “small list” of conditions his stem cell product could treat: arthritis, tendinitis, psoriasis, lupus, hair loss, facial wrinkles, scarring, erectile dysfunction, heart failure, cardiomyopathy, chronic obstructive pulmonary disease, asthma, emphysema, stroke, Alzheimer’s disease, multiple sclerosis, ALS, neuropathy, pelvic pain, diabetes, dry eye, macular degeneration, kidney failure. And that was just a sample. “I need to add a couple more slides,” Greene said with a laugh.

 

Greene said that amniotic stem cells derive their healing power from an ability to develop into any kind of tissue, but he failed to mention that mainstream science does not support his claims. He also did not disclose that he lost his license to practice medicine in 2009, after surgeries he botched resulted in several deaths. Instead, he offered glowing statistics: amniotic stem cells could help the heart beat better, “on average by 20%,” he said. “Over 85% of patients benefit exceptionally from the treatment.”

 

“Patients come back to the center saying, ‘I can walk farther, I can breathe easier, I can sleep better,’ ” he proclaimed. “It’s remarkable the outcomes we’ve been seeing for the last few years.”

 

In the second row, a slender woman in a striped jacket, who had hobbled into the meeting on a wooden cane, pumped her fists in the air. “Stem cells!” she cheered.

 

For more than half a century, the regenerative possibilities of stem cells — which the body stores to repair damaged tissue and organs and restore blood supply — have tantalized the medical community. Bone marrow transplants for cancer patients, which rely on blood stem cells, fulfill this potential. But alongside legitimate, scientifically proven treatments, an industry has sprung up in which specialized clinics offer miracle remedies from poorly understood stem cell products.

 

These clinics are multiplying in the United States. According to a tally by Leigh Turner, an associate professor of bioethics at the University of Minnesota, there were 12 such clinics advertising to consumers in 2009; in 2017, there were more than 700. Unproven cellular therapies are a $2 billion global business, according to a recent paper co-authored by Massimo Dominici, the lead investigator at the cellular therapy lab at the University of Modena and Reggio Emilia, in Italy.

 

This burgeoning business is largely unregulated. Technically, manufacturers are required to submit stem cell therapies for review as a drug, and to provide evidence of their safety and efficacy, but the U.S. Food and Drug Administration hasn’t enforced the rule consistently. The former FDA commissioner Dr. Scott Gottlieb acknowledged in an interview that the agency’s laissez-faire attitude has made it easier for stem cell clinics to proliferate. “This is an example where the FDA, for a long period of time, took enforcement discretion, then the field grew,” he said. “Then it becomes hard to step in and actually apply the regulation.”

 

Many clinics offer stem cells taken from a patient’s own bone marrow or fat. But they’re being challenged by…Continue Reading…

 

This article is a collaboration between ProPublica and The New Yorker.

 

Courtesy: ProPublica.org