Five Is Good; But Ten Is Better

May 16, 2017 in Health, Health Claims by Joyce Bunderson

The lead author on some research published in the International Journal of Epidemiology on 22 February is Dagfinn Aune Ph.D. Before today, I was entirely unfamiliar with Doctor Aune. He is an associate professor at Bjorkness University College, Oslo, Norway and also a Research Associate at the Imperial College in London. After reading a little about his work and a few of his publications, I’ve decided this is a wonderful researcher, who I will want to follow. He has expertise in epidemiology, oncology, nutrition and dietetics. I’m sufficiently impressed with what I’ve read; however, being on ResearchGate, a collaborative networking organization just adds to my positive opinion.

What first caught my attention, was stumbling upon his name in an extremely short reference to the February 22, 2017 article called: Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality – a systematic review and dose-response meta-analysis of prospective studies. (https://doi.org/10.1093/ije/dyw319)

The researchers were trying scientifically to strengthen the relationship and better define the dose-response relationship (how much fruit and vegetables you need to yield what kind of response). In short, essentially what the researchers did was to evaluate 95 studies to learn the relative risks for cardiovascular disease, total cancer and all-cause mortality as related to the intake of fruit and vegetables. In addition, they learned quite a bit about individual fruit and vegetable varieties.

Cardiovascular disease and cancer are the two most common causes of death worldwide. Considerable epidemiological studies have shown that a higher intake of fruit and vegetables is followed by lower risks of certain cancers, coronary heart disease and stroke. Because of these facts, many of us (and certainly the nutritional scientists) want to know a little more precisely “how much?” Aune, etal, do a terrific job telling why a more comprehensive study needed to be done; including the varying recommendations for fruit and vegetables, from around the world. If you want to get an idea of what a difficult undertaking this research was, you should read the methods section of their research. Holy mackerel!!! What a big job!!!

I’m going to skip trying to explain this massive study or their methods and just try to share how this may matter to you. What I think is a really important take-away from this study is this: They learned that the biggest reduction in risk is at the low end of intake. What that means is that if you are presently taking very little fruit and vegetables then you can get a big benefit by increasing your intake. If you are presently eating the ‘five-a-day’ style intake, consider doubling (10-a-day – 800g). That much of a “dose” of fruit and vegetables can reduce your risk of coronary heart disease, stroke, cardiovascular disease, and all-cause mortality much more – it can take you down to the lowest levels of risk. To reduce total cancer risk, an intake of 7.5 servings/day was where the “dosage” line fell.

Of course, increasing our fruit and vegetable intake can benefit our health in other ways not considered in Aune’s research; also, it can help our environment. But the main take-home lesson that I hope we’ll embrace is that consistently eating more fruit, vegetables and other plant foods does reduce our risk of the top two causes of morbidity and mortality. Although Aune’s study found that leafy greens, cruciferous vegetables, citrus fruits, apples and pears were specifically associated with reduced risk; including a large variety of fruit and vegetables is still a perfect place to start.

Aune says of the research; “It is clear that from this work that a high intake of fruit and vegetables hold tremendous health benefits, and we should try to increase their intake in our diet.”