Eating vegetable oils instead of saturated fats like butter does not lower the risk of heart disease or lead to a longer life, a US study has found.
- Study finds replacing saturated fat with vegetable oils does not lower risk of heart disease
- Dieticians say further study is needed before changes made to Australian dietary guidelines
- “Limited study group” included people in US mental hospitals and nursing homes
The study’s finding, published in the medical journal BMJ, challenged Australia’s dietary guidelines that recommend replacing saturated fats with vegetable oils.
However the Dieticians Association of Australia (DAA) said the study was unlikely to bring about any change to those guidelines.
Julie Gilbert, from the DAA, said that the study had made members of the association question some of the advice they had been giving to people, but that further research was needed.
“It certainly is an area that is definitely emerging, and we need to obviously look at it,” she said.
“However in saying that, we still support the Australian dietary guidelines, because currently they are based on the strongest evidence that we have available to us.
“And that still recommends that people do limit the amount of foods that are high in saturated fats, such as butter and cream and palm oil.”
The belief that replacing saturated fats with vegetable oils is better for a healthy heart comes from evidence showing it reduces blood cholesterol levels.
Lennert Veerman, a senior lecturer at the University of Queensland’s school of public health, wrote an editorial about the research in the BMJ and said further study was needed before the Australian Dietary Guidelines could be changed.
“Other evidence, and that’s more following people up and seeing what they eat and then seeing their risk of heart disease, [is needed] then to support the hypothesis that avoiding saturated fat is good for health,” Dr Veerman said.
Dr Veerman said the national dietary advice might need to be tweaked slightly.
“But again, the experts need to discuss that and weigh all the evidence that there is, so for the moment it’s best to stick with what we have,” he said.
Study group limited, may not apply to whole population
The US study was based on an experiment that was done in the 1970s.
For more than four years almost 9,500 Americans who were living in mental hospitals and nursing homes were given a diet where they either ate saturated fats, such as butter, or got their fat from vegetable oils.
Ms Gilbert said it was a limited study group.
“We do need to look at the population group that this research looked at,” she said.
“And the research focuses on participants who are in a state mental hospital or a nursing home environment.
“So we need to know … is that just a unique population group or does that apply to the whole general population?
“When we’re talking about Australian dietary guidelines, they are used for the whole population.”
The DAA says Australians should try to avoid eating too much fat, because that helps people maintain a healthy weight and protect them against chronic disease.