Fad diets can work, but experts find no magic slimming bullet

January 13, 2014

Resolutions to lose weight are often made in January yet almost as frequently abandoned as heavy hopefuls find diets that demand fasting, virtually no carbs or liquid food shakes notoriously hard to stick to. But even "fad" diets can lead to a slimmer, lighter New Year for those whose resolve remains robust, according to doctors and nutritionists analysing them.

Gathering for a London conference to review evidence behind popular weight loss diets - at just the time of year when slimming ideas are in peak demand - specialists concluded that food fads such as the hunter-gatherer "Paleo" plan or the 5:2 diet can deliver. But it's hard work. "If it was easy, our species would have died out years ago. As humans we have a default to eat," said Gary Frost, a professor and chair of nutrition and dietetics at Imperial College London. The results of that default are looming large in a global "wave of obesity", he said. According to the World Health Organisation, worldwide obesity - defined as having a body mass index of more than 30 - has nearly doubled since 1980. The latest global figure is that in 2008, more than 1.4 billion adults were overweight.

WAVE OF OBESITY

According to the US Centers for Disease Control and Prevention, almost 36% of American adults are obese and almost 70% are either obese or overweight. In Britain, a government health study predicts 60% of men, 50% of women and 25% of children will be obese by 2050. Against this background, experts say the search for effective diets must always take account of how easy it is for people to understand and follow, and how likely they are to abide by its restrictions.

Michelle Harvie, a research dietician from the Genesis Prevention Centre at Britain's University Hospital of South Manchester, said that on this front, fasting diets - sometimes called intermittent diets - can be successful. "Energy restriction is difficult to maintain over the long term and people tend to find it easier to follow a diet with intermittent energy restriction," she said. She said that while a regular weight loss plan might require the dieter to take in 25% fewer calories, intermittent diets may suggest two days of a 75% calorie cut interspersed with five days of normal healthy eating. But the key to these diets - such as the 5:2 diet in which followers eat as little as 400 calories on two "fasting" days per week - is that dieters won't succeed if they "pig out" and eat whatever they want on non-fasting days.

Harvie's research shows those who succeed in losing weigh on these diets find the fasting days lead them to also have a lower food intake on normal days - leading to lower calorie intake overall.

HUNTING FOR FOOD

Mark Berry, head of plant biology and biochemistry at the consumer company Unilever's research and development unit, says there are also positive signs in data from studies of "Palaeolithic" or stone-age diets - plans designed to mimic the diet of pre-agricultural hunter-gatherers of that era. A sign of its current popularity is that "Paleo diet" was one of the most "Googled" terms of 2013.

The idea is based around foods that can be hunted, fished or foraged for - meat, seafood, eggs, nuts, seeds, fruits and vegetables. Berry said his research showed little impact on glucose response in the body in people eating a Palaeolithic diet, but did find a significant impact on hormones that signal satiety and tell the brain the eater is full. Alexandra Johnstone of the Rowett Institute of Nutrition and Health, who has been looking into high protein and low carbohydrate diets such as the Atkins diet, said these also had a significant impact on fullness feelings - giving them the potential to help dieters control appetite and lose weight. "The high satiety effects of increased protein in the diet seems to be a contributing factor to the success of high-protein, low-carbohydrate diets," she said.

Johnstone cited data showing the amount of weight lost on high-protein diets is around double that lost on a comparable low-fat diet at the six-month mark. But there is little difference in weight loss after one year, as dieters often lose momentum and their resolve to slim down fades. "There's no magic bullet," she said. Judy Buttriss, head of the British Nutrition Foundation, said the evidence for popular diets was clearly nuanced. While there are several that can be used as tools for effective weight loss and maintenance, she said "there's currently no evidence that one is any better than another in the long term".

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Agencies
May 19,2020

New York, May 19: Cigarette smoke spurs the lungs to make more of the receptor protein which the novel coronavirus uses to enter human cells, according to a study which suggests that quitting smoking might reduce the risk of a severe coronavirus infection.

The findings, published in the journal Developmental Cell, may explain why smokers appear to be particularly vulnerable to severe COVID-19 disease.

"Our results provide a clue as to why smokers who develop COVID-19 tend to have poor clinical outcomes," said study senior author Jason Sheltzer, a cancer geneticist at Cold Spring Harbor Laboratory in the US.

"We found that smoking caused a significant increase in the expression of ACE2, the protein that SARS-CoV-2 uses to enter human cells," Sheltzer said.

According to the scientists, quitting smoking might reduce the risk of a severe coronavirus infection.

They said most individuals infected with the virus suffer only mild illness, if they experience any at all.

However, some require intensive care when the sometimes-fatal virus attacks, the researchers said.

In particular, they said three groups have been significantly more likely than others to develop severe illness -- men, the elderly, and smokers.

Turning to previously published data for possible explanations for these disparities, the scientists assessed if vulnerable groups share some key features related to the human proteins that the coronavirus relies on for infection.

First, they said, they focused on comparing gene activity in the lungs across different ages, between the sexes, and between smokers and nonsmokers.

The scientists said both mice that had been exposed to smoke in a laboratory, and humans who were current smokers had significant upregulation of ACE2.

According to Sheltzer, smokers produced 30-55 per cent more ACE2 than their non-smoking counterparts.

While the researchers found no evidence that age or sex impacts ACE2 levels in the lungs, they said the influence of smoke exposure was surprisingly strong.

However, they said, the change seemed to be temporary.

According to the data, the level of the receptors ACE2 in the lungs of people who had quit smoking was similar to that of non-smokers.

The study noted that the most prolific producers of ACE2 in the airways are mucus-producing cells called goblet cells.

Smoking is known to increase the prevalence of such cells, the scientists said.

"Goblet cells produce mucous to protect the respiratory tract from inhaled irritants. Thus, the increased expression of ACE2 in smokers' lungs could be a byproduct of smoking-induced secretory cell hyperplasia," Sheltzer explained.

However, Sheltzer said other studies on the effects of cigarette smoke have shown mixed results.

"Cigarette smoke contains hundreds of different chemicals. It's possible that certain ingredients like nicotine have a different effect than whole smoke does," he said.

The researchers cautioned that the actual ACE2 protein may be regulated in ways not addressed in the current study.

"One could imagine that having more cells that express ACE2 could make it easier for SARS-CoV-2 to spread in someone's lungs, but there is still a lot more we need to explore," Sheltzer said.

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Agencies
June 20,2020

At a time when the country is yet to recover from the shock of losing 20 Indian soldiers in a violent clash with the Chinese People's Liberation Army (PLA) troops in Ladakh's Galwan Valley, another shocker has come to light with news coming of a malware hitting the Indian Railways network and snooping its data for foreign countries, including train movements, sources in the intelligence agencies said on Friday.

Meanwhile, Railways Board Chairman V K Yadav said that the national transporter keeps on receiving malware security threats and the engineers in the railways keep on taking all precautions and keeps on updating the firewalls to prevent data theft.

The news comes a day after the Dedicated Freight Corridor Corporation Limited (DFCCIL) decided to terminate the 417-km signalling project worth Rs 471 crore with Chinese firm Beijing National Railway Research and Design Institute of Signal and Communication Group Company Limited (BNRRDISC) due to non-performance.

According to intelligence agency sources, the system of the Railways has been hit by the APT 36 Malware campaign. The source said that the intel agencies have also alerted the Railway Board to instantly disconnect the system with the Internet and change the password immediately.

The source said the APT 36 Malware is connected to Pakistan, which is a close ally of China. The source further said that following the red flag from the intel agencies, the system of a senior Principal Executive Director of the Railways, working in its vigilance department, has been taken for cleaning the malware threat.

As per the source, through the APT 36 Malware campaign, data stored in the Indian Railways systems were being stolen and stored in foreign locations, including the movement of the trains.

He further claimed that the APT 36 Malware also tried to take defence movement data. 

The source said the APT 36 Malware effect was reported from at least four systems of the Indian Railways.

Responding to queries, the Railways Board Chairman said: "Whether it is our systems or the IRCTC, we continuously update it with firewalls, and it is an ongoing process as we get the updates." 

Yadav said that our system is updated time to time. "We get malware threat on a regular basis. And we look at it continuously," he said. 

When pressed further about the malware threat in four railways systems, he said: "It has not come to our notice that some information has been leaked. Our systems are secure and our engineers keep on working on it."

According to intel sources, besides Railways, there was also malware threat in the defence, central police organisations, education and healthcare sectors, the source said.

In view of the threat, the intel agencies have asked the departments concerned to change the passwords of emails and online services from secure computers, format the hard-disk of the affected computers after taking back-up and re-install the operating systems and other softwares.

Sources in the Railways had said on Thursday that DFFCIL, which is looking after the work of the Dedicated Freight Corridor Project, has decided to terminate the tender with BNRRDISC.

A source in the Railway Ministry said that it has informed the Railway Board and the World Bank to take the final decision in the matter.

The source said the project was awarded to the Chinese firm in 2016 for signalling and telecommunication work on the 417-km Kanpur-Deen Dayal Upadhyaya section of the Eastern Dedicated Freight Corridor (EDFC). 

The source disclosed that the contract was awarded to the Beijing National Railway Research and Design Institute in June 2016. The source further said that even after four years, the progress in the project was only 20%. The issues that led to the termination of the project are reluctance by the company to furnish technical documents, as per the contract agreement, such as logic design of electronic interlocking.

The source further said that other issues like non-availability of their engineers and authorised personnel on site were a serious constraint. Even physical work could not progress as they have no tie-up with local agencies. 

The 3,373-km DFC, a flagship project of the Railways, aims to augment rail transport capacity to meet the growing requirement of movement of goods by segregating freight from passenger traffic.

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Agencies
April 4,2020

Washington D.C., Apr 4: While consuming a high-diet salt can result in high blood pressure, a recent study has revealed a link between salt-rich diet and weaker immune system.

The study was conducted under the leadership of the University Hospital Bonn, and the results were published in the journal Science Translational Medicine.

The research was conducted on mice that were fed a high-salt diet. Later, they were found to suffer from much more severe bacterial infections.

Human volunteers who consumed an additional six grams of salt per day also showed pronounced immune deficiencies.

The World Health Organization (WHO) has recommended a maximum amount of five grams of salt a day.

It corresponds approximately to one level teaspoon. In reality, however, many Germans exceed this limit considerably. 

Figures from the Robert Koch Institute suggest that on average men consume ten, and women more than eight grams a day.

This means that we reach for the salt shaker much more than is good for us. After all, sodium chloride, which is its chemical name, raises blood pressure and thereby increases the risk of heart attack or stroke.

"We have now been able to prove for the first time that excessive salt intake also significantly weakens an important arm of the immune system," said Prof. Dr. Christian Kurts from the Institute of Experimental Immunology at the University of Bonn.

This finding is unexpected, as some studies point in the opposite direction. For example, infections with certain skin parasites in laboratory animals heal significantly faster if these consume a high-salt diet.

The study also sheds light on the fact that the skin serves as a salt reservoir.

"Our results show that this generalization is not accurate," emphasized Katarzyna Jobin, lead author of the study.

The body keeps the salt concentration in the blood and in the various organs largely constant. Otherwise important biological processes would be impaired. The only major exception is the skin which functions as a salt reservoir of the body. This is why the additional intake of sodium chloride works so well for some skin diseases.

However, other parts of the body are not exposed to the additional salt consumed with food. Instead, it is filtered out by the kidneys and excreted in the urine.

"We examined volunteers who consumed six grams of salt in addition to their daily intake," said Prof. Kurts. This is roughly the amount contained in two fast-food meals, i.e. two burgers and two portions of French fries.

After one week, from the results, it showed that the immune cells coped much worse with bacteria after the test subjects had started to eat a high-salt diet.

In human volunteers, excessive salt intake also resulted in increased glucocorticoid levels.

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