RISK: Not eating enough of these six healthy foods is associated with higher cardiovascular disease and deaths globally…

By WSAM Correspondent

HAMILTON, ON (July 6, 2023) – A study led by McMaster University and Hamilton Health Sciences researchers at the Population Research Health Institute (PHRI) has found that not eating enough of six key foods in combination is associated with a higher risk of cardiovascular disease (CVD) in adults.

Consuming fruits, vegetables, legumes, nuts, fish and whole-fat dairy products is key to lowering the risk of CVD, including heart attacks and strokes. The study also found that a healthy diet can be achieved in various ways, such as including moderate amounts of whole grains or unprocessed meats.

Previous and similar research has focused on Western countries and diets that combined harmful, ultra-processed foods with nutrient-dense foods. This research was global in scope and focused on foods commonly considered to be healthy.

The World Health Organization estimates nearly 18 million people died from CVD in 2019, representing 32 per cent of all global deaths. Of these deaths, 85 per cent were due to heart attacks and strokes. PHRI researchers and their global collaborators analyzed data from 245,000 people in 80 countries from multiple studies. The results were published in the European Heart Journal on July 6.

Researchers derived a diet score from PHRI’s ongoing, large-scale global Prospective Urban and Rural Epidemiological (PURE) study, then replicated that in five independent studies to measure health outcomes in different world regions and in people with and without prior CVD.

“Previous diet scores – including the EAT-Lancet Planetary Diet and the Mediterranean Diet tested the relationship of diet to CVD and death mainly in Western countries. The PURE Healthy Diet Score included a good representation of high, middle, and low-income countries,” said Salim Yusuf, senior author and principal investigator of PURE.

As well as being truly global, the PURE Healthy Diet Score focused on exclusively protective, or natural, foods.

“We were unique in that focus. The other diet scores combined foods considered to be harmful – such as processed and ultra-processed foods – with foods and nutrients believed to be protective of one’s health,” said first author Andrew Mente, PHRI scientist and assistant professor at McMaster’s Department of Health Research Methods, Evidence, and Impact.

“There is a recent increased focus on higher consumption of protective foods for disease prevention. Outside of larger amounts of fruits, vegetables, nuts and legumes, the researchers showed that moderation is key in the consumption of natural foods,” he said.

“Moderate amounts of fish and whole-fat dairy are associated with a lower risk of CVD and mortality. The same health outcomes can be achieved with moderate consumption of grains and meats – as long as they are unrefined whole grains and unprocessed meats.”

The PURE Healthy Diet Score recommends an average daily intake of: Fruits at two to three servings; vegetables at two to three servings; nuts at one serving; and dairy at two servings. The score also includes three to four weekly servings of legumes and two to three weekly servings of fish. Possible substitutes included whole grains at one serving daily, and unprocessed red meat or poultry at one serving daily.

There was no specific funding for this analysis, although each study that contributed data was funded separately and conducted over a 25-year period.

WATER FASTS: THE PROS AND CONS

BENEFITS: They can help you lose weight, but you might gain it back quickly…

By Emily Stone

Water fasts — where people consume nothing but water for several days — might help you lose weight, but it’s unclear how long you’ll keep it off, according to research from the University of Illinois Chicago. And the other metabolic benefits of water fasts, such as lower blood pressure and improved cholesterol, seem to disappear soon after the fast ends, the researchers found.

However, there do not appear to be any serious adverse effects for those who do a water fast or a similar kind of fast where people consume a very small number of calories a day, said Krista Varady, professor of kinesiology and nutrition, who led the research, which is published in Nutrition Reviews.

“My overall conclusion is that I guess you could try it, but it just seems like a lot of work, and all those metabolic benefits disappear,” Varady said. She stressed, however, that no one should undertake one of these fasts for more than five days without medical supervision.

Varady, an expert on intermittent fasting, said she wanted to study water fasting because she suddenly started getting contacted by journalists last fall who wanted to hear what she thought about it. She figured if she was going to comment, she should investigate the existing research.

The new paper is a literature review of eight studies on water fasting or Buchinger fasting, a medically supervised fast that is popular in Europe where people consume only a tiny amount of juice and soup a day. Varady’s team looked at the results from each of those papers to see what story they cumulatively tell about the fasts’ impact on weight loss, as well as a number of other metabolic factors.

Fasting did seem to spur noticeable short-term weight loss, the researchers found. People who fasted for five days lost about 4% to 6% of their weight; those who fasted for seven to 10 days lost about 2% to 10%, and those who fasted for 15 to 20 days lost 7% to 10%.

Only a few of the studies in the review tracked whether participants gained back the weight they had lost once the fast ended. In one of those, people gained back all they had lost in a five-day water fast within three months. In two other studies, only a small amount of the lost weight returned, but those studies encouraged participants to restrict their calorie intake after the fasts ended.

In contrast, it was clear that the metabolic benefits of the fasts disappeared soon after the fasts ended. Improvements to blood pressure, cholesterol and blood sugar levels were short-lived, returning to baseline levels quickly after participants started eating again. Some of the studies included participants with Type 1 and Type 2 diabetes, who suffered no ill effects from the fasting, though they were monitored closely and had their insulin doses adjusted while fasting.

The most common side effects of these prolonged fasts were similar to those from intermittent fasting, Varady said, such as headaches, insomnia and hunger. There were no serious negative effects in the studies, such as metabolic acidosis or death.

She did note that the participants in these prolonged fasts lost about two-thirds of their weight in lean mass and one-third in fat mass. This is the opposite of what happens most of the time during weight loss, where more fat is lost than muscle. It makes sense that these extreme fasts would have this result, she said, because “your body needs a constant intake of protein. If it doesn’t have that, then it draws from muscles.”

Varady’s research into intermittent fasting has looked at how well the regime works for weight loss, as well as at specific questions, such as whether intermittent fasting affects fertility — she found it does not.

Varady said she would encourage someone hoping to lose weight to try intermittent fasting instead of a water fast, “because there’s a lot more data to show it can help with weight management,” she said.