You can't exercise away poor dietary choices,study finds

 

• A new study finds that exercising to make up for eating poorly doesn’t really work in terms of lowering mortality risks.
• Similarly, eating well but remaining inactive may help lower your risk of dying from certain cancers to a degree, but does nothing for all-cause or cardiovascular disease mortality, the researchers found.
• Researchers also observed that those who exercised the most and consumed the healthiest food significantly reduced their risk of dying from all causes, from cardiovascular disease, or from certain cancers.

There has been a lot of conversation — and a great deal of research — attempting to determine whether exercise or a healthy diet is more important for longevity. A new study led by researchers from the University of Sydney in Australia analyzing UK Biobank data may provide the answer.

Researchers found that people who engaged in high levels of physical activity and also ate a high quality diet had lower mortality risks.

For anyone who believed that one can exercise away poor dietary choices, this study suggests otherwise.

People who engage in one or the other lowered the risk of mortality to a lesser degree. Study corresponding author, associate professor Dr. Melody Ding, told Medical News Today:

“These groups still do better (and statistically significant) than the group with poor diet and lowest physical activity, but the group with the best diet and moderate or high physical activity levels do the best!”

The study focused on deaths due to all-cause mortality, cardiovascular disease (CVD), and adiposity-related (PDAR) cancersTrusted Source.

Cardiology dietician Michelle Routhenstein, who specializes in heart health, and was not involved in the study, told MNT:

“The study results are no surprise to me. Many people have come to see me in my private practice after suffering a heart attack when training for their fourth or fifth marathon, or right after doing a CrossFit exercise.”

“When I do a comprehensive evaluation of their lifestyle, it is apparent that they thought their intense daily exercise regimen would make up for their poor, unbalanced diet, and it simply doesn’t.”
— Michelle Routhenstein, cardiology dietician

The study is published in BMJ Sports Medicine.

Analyzing exercise and diet habits

The researchers analyzed existing health records for 346, 627 U.K. residents that enrolled in the UK Biobank between April 2007 to December 2010. The health of these individuals was followed for an average of 11.2 years. For this study, the UK Biobank data were linked to the National Health Service death records until 30 April 2020.

For the purposes of their analysis, researchers considered the number of minutes people engaged in walking, moderate-to-vigorous physical activity (MVPA), and vigorous-intensity physical activity (VPA). For both MVPA and VPA, they used a 1-4 ranking system.

A high quality diet consisted of 4.5 cups or more of vegetables or fruit per day, two or more servings of fish weekly, and less than two servings of processed meat or less than five servings of red meat weekly.

The selection of target foods reflects recommendations from the American Heart Association, with the authors noting:

“These food groups were selected as markers for overall diet quality because other important dietary components and/or nutrient groups, such as whole grains and dairy, were not measured during baseline assessment.”

The researchers rated the individuals’ diet quality poor, medium, or one of two levels of best.

The best results

Compared to physically inactive individuals who ate the lowest-quality diet, those engaging in the highest activity levels and eating the highest-quality diet reduced their risk of all-cause mortality by 17%. They also reduced their mortality risk of cardiovascular disease by 19% and of PDAR cancers by 27%.

The higher the level of MVPA, the greater the reduction in all-cause and PDAR cancer mortality risk, with the most active group attaining a 13% to 14% reduction over the least active group.

The same was true for VPA, although it also had a beneficial effect on cardiovascular disease mortality risk. However, the two middle levels curiously reduced individuals’ risk more than the highest level of activity.

As for the reason behind vigorous activities’ larger effect on cardiovascular disease mortality risk, the authors note:

“It has been argued that VPA may lead to more physiological adaptations and elicit more insulin-sensitizing and anti-inflammatory effects than lower-intensity physical activity, which may explain why the stronger association with VPA are particularly pronounced for CVD mortality in our study.”

The highest-quality diet by itself — without MVPA or VPA — had no statistically significant bearing on all-cause mortality risk or cardiovascular mortality risk. It did, however, reduce their chances of PDAR cancer mortality by 14%.

In terms of the interaction between physical activity and diet, Dr. Ding said, “Diet plays a similar role in mortality risk in those who are physically active and those who are inactive, and vice versa.”

Living longer

As far as optimizing one’s chance of a long life based on the study’s insights, Dr. Ding said:

“I guess the simplest answer is to adhere to public health guidelines, such as The Eatwell Guide for eating, and the WHO guidelines on physical activity and sedentary behaviorTrusted Source. These guidelines are based on solid evidence.”

Taking physical activity and diet separately, Routhenstein noted:

“I need to assess where the person is in their exercise journey, their medical conditions, and their limitations to guide them appropriately. Too much too fast or too heavy of intensity both in aerobic or anaerobic exercise can lead to negative side effects.”

“When it comes to exercise, we are looking ideally for 150 to 225 minutes of weekly moderate-intensity cardiovascular activity, about 60 minutes of low to medium intensity resistance exercise and regular stretching. [Start] your day with a balanced breakfast and [have] therapeutic foods, such as lean protein, vegetables and fruits, whole grains, nuts, seeds, and legumes, in line with your hunger/satiety cues.”

— Michelle Routhenstein, nutritionist

“In order for your diet to be truly heart healthy, it needs to be long-lasting,” added Routhenstein. “Quick fixes do not work, and starting a diet plan that won’t last long term isn’t effective.”

Regular vigorous or moderate exercise linked to lower risk of death

• Regular exercise is associated with a reduced risk of cardiovascular disease and premature death. However, there was limited evidence looking at the impact of exercise intensity on these risks.
• A new analysis of over 100,000 participants, reviewed over a 30-year follow-up period, has shown that vigorous or moderate exercise is linked to the lowest risk of death.
• Experts say taking small steps to move more can help one improve their health, and it’s important for individuals to consider their own unique circumstances and physical ability.

It is well known that being physically active can help you lead a healthier and happier life. People who exercise regularly have a lower risk of developing several long-term (chronic) conditions, such as heart disease, type 2 diabetes, and some cancers. Studies showTrusted Source that physical activity also boosts self-esteem and mood, and can also help people to have better quality sleep. However, while getting enough exercise is important, the intensity of the exercise should also be considered.

A recent analysisTrusted Source published in Circulation investigated the link between long-term physical activity intensity and the risk of death.

The study found that adults who perform two to four times the currently recommended amount of moderate or vigorous physical activity per week had a significantly reduced risk of death.

The 2018 physical activity guidelinesTrusted Source recommend that adults engage in at least 150 to 300 minutes of moderate physical activity per week, and 75 to 150 minutes of vigorous physical activity per week. However, a growing number of people are performing higher levels of more vigorous exercise to maintain health and improve fitness. For example, high intensity interval training (HIIT) has become increasingly popular.

However, there have concerns about the potentially harmful effects on the cardiovascular health of an excessive amount of vigorous physical activity. Although, there is limited and sometimes conflicting evidenceTrusted Source to support this.

This new research, conducted by Lee et al., involved analyzing data from 2 large cohorts of participants: the Nurses’ Health Study and the Health Professionals Follow-up Study, collected from 1988-2018.

In these cohorts, participants completed questionnaires about their physical activity up to 15 times during the follow-up period. They were asked to report the average hours they spent on various activities, including walking, jogging, running, swimming, bicycling, aerobic exercise, playing squash/racketball or tennis, while also logging low intensity exercise and weightlifting.

Study author Dr. Dong Hoon Lee explained to Medical News Today the implications of this research for people who want to increase their own activity levels.

“Our study showed that many people can get significant health benefits by performing the recommended physical activity (150 minutes per week of moderate activity or 75 minutes per week of vigorous activity) so it is important to stay active. For those who are looking for the optimal health benefits from exercise, they can aim for higher levels of activity (2+ times the recommended level).”

– Dr. Dong Hoon Lee

Benefits of moderate and vigorous exercise

The analysis showed that the greatest benefit for reducing the risk of death was observed among people who reported around 150 to 300 minutes per week of vigorous physical activity, 300 to 600 minutes per week of moderate physical activity, or an equivalent combination of both.

Prof. Becca Krukowski of the University of Virginia, who was not involved in the study, explained to Medical News Today how this research has real-world implications for people looking to improve their own health.

“These results indicate that either moderate and vigorous physical activity can have positive benefits for longevity and health. These results are consistent with previous research indicating that 300 minutes or more of moderate-to-vigorous physical activity may be necessary for those who wish to maintain a weight loss,” said Prof. Krukowski. 

Study implications and limitations

The large study population, long follow-up time, and the regularity of the data collection (from the self-reported questionnaires) were considered to be strengths of the study.“The authors did a nice job conducting sensitivity analyses that addressed many potential limitations. However, the type of physical activity—moderate or vigorous—was based on self-reported categories of activities,” said Krukowski. “For example, cycling was assumed to always be vigorous, but cycling could also be of moderate intensity.”Prof. Catherine A. Sarkisian, Director of the UCLA Value-Based Care Research Consortium, who was also not involved in this research, explained to Medical News Today that for those who already meet the recommended guidelines of 150 to 300 minutes of moderate physical activity or 75 to 150 minutes of vigorous physical activity, there appears to be an added benefit of doing higher levels of vigorous physical activity (up to 600 minutes of moderate or 300 minutes of vigorous physical activity).

“We now have even stronger evidence than previously that exercising in mid-life will probably help you live longer,” Prof. Sarkisian noted.

In addition, for people who only do moderate but never vigorous physical activity, there appears to be an added benefit to adding 25% of the time doing a vigorous physical activity rather than only doing moderate physical activity.

If you are a walker who never breaks a sweat, you might try adding some speed intervals or walking briskly up hills,” Prof. Sarkisian said.

However, on reviewing the study participants recruited for the study, Prof. Sarkisian noted that the studies included mostly non-Latino white people, a major limitation.

“It is very important to keep in mind that because this was not a clinical trial, we cannot be sure that it was the exercise itself that caused longer life rather than other factors associated with exercise. People who exercise are likely to be healthier in other ways that were not measured in this study, so the large effect sizes should be interpreted with caution.”

– Prof. Catherine A. Sarkisian

Small steps to increase physical activity levels

The study’s findings support the current physical activity guidelines and also suggest that higher levels of long-term vigorous and moderate exercise provide the most benefit in reducing the risk of death.

However, it’s important for individuals to consider their own unique circumstances and physical ability.

Not everyone is able to undertake vigorous exercise, but taking small steps to move more can help most people work toward improving their health.

Consider walking whenever possible instead of driving. Take the stairs instead of using the elevator. Go for an extra walk in the evening after dinner.

You can also do more inside your home, like gardening, yard work, or washing the car. Try to live as actively as possible, perhaps by doing sit-ups in front of the television or joining a local walking club. These small steps will make a positive impact on your health.

Prof. Krukowski had the following advice for people who want to increase their physical activity levels, but are unsure where to start:

Find a type of physical activity that you enjoy. That way, you’re more likely to continue with it.

Some people love being active in a group (like a cycling group or an exercise class), while others prefer to be active alone. Do what works for you.

Try pairing physical activity with something you enjoy, like listening to music or podcasts, talking with a friend, or watching your favorite show.

Although increasing exercise levels may sometimes feel overwhelming, it’s important to remember that any additional activity will help.

By doing activities a person enjoys, they’re much more likely to continue with it.

Ultimately, it’s important to figure out what works for the individual.

Source -Medical News Today