Candy, White Bread, Butter Linked to Poor Heart Health

It’s common for studies on diet and heart health to focus on specific nutrients, but it’s more common for dietitians to talk about whole dietary patterns. That’s because diets are varied, and what we eat as a whole has more impact on our health than any individual food.

In a new study published in BMC Medicine, researchers in the United Kingdom wanted to identify the food-based dietary patterns associated with an increased risk of developing cardiovascular disease (CVD).

Previous Research and Guidelines

There have been many studies on individual foods and their effect on heart health—everything from butter to eggs to almonds has been intricately examined. But aside from the Mediterranean diet, there is not a lot of scientific evidence about overall diet or dietary patterns for heart health, says Carmen Piernas, senior researcher at Nuffield Dept Primary Care Health Sciences at the University of Oxford and one of the authors of the study.

She notes that nutrient-focused thinking is still reflected in many dietary guidelines, including those in the US and the UK, where we find messages such as ‘eat less added sugar’ or ‘eat less saturated fat.’

“We hope our study will make people think in terms of foods and not nutrients, and hopefully guidelines will follow on this work to try and provide guidance for these specific foods which have a link with increased CVD and mortality,” says Piernas. 

Why Look at Specific Foods in Dietary Patterns?

A poor dietary pattern contributes to cardiovascular disease by raising cholesterol levels and increasing the risk of type 2 diabetes and high blood pressure.

As a public health measure, it’s important to communicate the specific foods within dietary patterns that are potentially problematic when consumed in excess. In this case, it’s more helpful to tell the public to cut back on butter, fatty meat, and ice cream than say ‘cut back on saturated fat’ since people may not know which foods contain this nutrient.

“Here, we have identified specific foods within an overall dietary pattern which contribute to the risk of CVD and mortality among British people,” says Piernas. “So the most important point is to get people thinking about reducing the amount of chocolate, confectionery, butter, and white bread they eat, instead of reducing sugars or saturated fat.”

What Did the Study Show?

For the study, Piernas and the research team collected dietary data from over 116,000 UK residents on two or more occasions, then followed up over a period of 4.9 years (on average) to monitor cases of CVD. Then they compared different dietary patterns with CVD outcomes. 

During follow up, there were:       

• 4,245 cases of total CVD
• 838 cases of fatal CVD
• 3,629 cases of all-cause mortality

The researchers noted a positive linear association between total CVD and a dietary pattern high in candy and chocolate, butter, low-fiber white bread but low regarding vegetables, fruit, and whole grains intake.

A second dietary pattern linked to CVD was high in sugar-sweetened beverages, fruit juice, table sugar, and jam and low in butter, vegetables, and whole grains.

Note that this study set out to map associations but does not prove cause and effect.

Piernas adds that the findings were not surprising because these dietary patterns are really high in saturated fat, free sugars, and energy density, which are concerns for health.

Kelsey Lorencz, a Michigan-based registered dietitian at Graciously Nourished, agrees.

"The results of this study are not surprising at all,” says Lorencz. “We only have so much capacity for food in a day. When we fill up on sweets and nutrient-depleted foods like refined breads and sugary snacks, there isn't much room for vegetables, fruits, and whole grains, which are full of heart-healthy fiber, vitamins, minerals, and antioxidants.” 

Saturated Fat and Sugar in Focus

Large nutrition organizations, such as the American Heart Association, have historically recommended limiting saturated fat intake to promote heart health. Some recent studies have found no beneficial effect on heart health when reducing butter or overall saturated fat intake.

In the present study, the first dietary pattern showed that butter had a negative effect. However, the second dietary pattern showed CVD risk associated with a high intake of sugar, but a low intake of butter. 

Interestingly, the people with the high sugar diet also had healthier overall behaviors. They were more physically active, had lower alcohol intake, less smoking, and their intake of saturated fat met the recommended levels.

The study showed that people in the highest quintile for the sugary dietary pattern had increased risks for CVD and all-cause mortality. They consumed about 17 percent of calories from sugars, which is more than three times the UK dietary guideline. And they only consumed 10 percent of calories from saturated fat, which is the recommended level.

It looks like a case of increasing one nutrient of concern (sugar) at the expense of another (saturated fat), but the net effect is that too much sugar is bad for heart health, even in the absence of excess saturated fat.

“People don’t eat nutrients in isolation, we eat foods that have combinations of many different nutrients,” says Piernas. “Our research still confirms that saturated fat is important for cardiovascular disease, but our results need to be kept in the context of the whole diet, so high saturated fat, together with high free sugars and calories and low fiber is certainly important for CVD and all-cause mortality risk.”

Get More Whole Grains and Vegetables

Increasing your intake of fruits, vegetables, and whole grains is a great way to promote optimal heart health. Lorencz works with clients to help them focus on healthy eating patterns, including plant-based eating, instead of focusing on individual nutrients.

“I'm a huge advocate for plant-based eating,” says Lorencz, who explains that eating more plant-based foods can help increase fiber and decrease saturated fats.

“Plant-based eating doesn't mean you never eat animal foods, but the focus is on plants; whole grains, legumes, fruits, and vegetables,” says Lorencz. “This pattern of eating helps to lower blood cholesterol levels with its abundance of fiber and low intake of saturated fats.” 

The latest Dietary Guidelines for Americans 2020-2025 did include some food-based recommendations, especially regarding fruits and vegetables, but nutrient-based advice (such as ‘eat less saturated fat’) still prevails. In the future, dietary guidelines that focus on foods and dietary patterns rather than individual nutrients could help avoid consumer confusion.