Fruit & veg is a marker, not maker, of health

I’ve said in a number of posts (here and here, for example) that fruit and veg intake is a marker of health, not a maker of health. Healthy people eat fruit and veg; fruit and veg does not make people healthy.

One of the best illustrations of this can be seen in Table 1 of this paper.

This table has the characteristics of the study participants grouped into fruit and veg intake. If you compare the column of the (9,897) people who consume no fruit and veg, or less than 1 portion a day, with the column of the (6,037) people who consume more than 7 portions a day, you can see the following differences. Those consuming more than 7-a-day are:

  • Twice as likely to be in non-manual jobs.
  • Four times as likely to be degree educated.
  • A quarter as likely to be a current smoker.
  • A quarter as likely to be inactive.
  • Twice as likely to be vigorously active.
  • Half as likely to drink over double the daily limit.
  • Half as likely to die (during the study period).

Epidemiological studies, such as this one (and more appear every week) would like you to believe that the fruit and veg is the cause of the lower mortality/fewer incidents of disease – whatever this week’s paper tries to show. They claim that they have adjusted for “sex, age-group, cigarette smoking, social class, BMI, education, physical activity and alcohol intake.” But you cannot adjust for a whole lifestyle.

Picture the woman (because it is more likely a woman) who eats at least 7-a-day – educated, well-paid, company executive, slim, never smoked, occasionally drinks, snacks on mango slices on the way to the Pilates class, before picking Charlotte and George up from private school. Then picture the factory worker – the manual worker (if he’s lucky enough to have a job), left school at 16, smoking, drinking, largely sedentary, dad – worried about feeding the family – who didn’t eat a single item of fruit or veg yesterday. That’s what Table 1 describes. These studies are about health inequalities, not phytonutrients!

As I said in my seven-a-day post “Do researchers really think that we could take a Glaswegian man or woman – with a life expectancy of 71.6  and 78 respectively – and give them the life expectancy of the men and women in Kensington and Chelsea – 85.1 and 89.8 respectively – with extra portions of fruit and vegetables? May I suggest that the fruit and veg intake is a marker of a healthy lifestyle and not the maker of one?”

4 thoughts on “Fruit & veg is a marker, not maker, of health

  • Haha. As my son says, not surprising, as we are not orang outangs.

  • From this food diary article in The Times on the same day, where the writer tries to consume his 10 a day. He should not have been surprised by the result: [The nurse thinks the
    fibre might be fattening?!]
    “Before I started my ten-a-day week, Bupa conducted a health assessment — weight, body fat, cholesterol — and said that although one week was probably too short a time to detect any significant changes, I should feel “brighter”. I just feel fuller from the endless snacking on fruit.
    “Your bowel habits could certainly improve within a week,” Dr Steve Iley, Bupa’s medical director, added.
    Now, I don’t like to boast, but Mussolini could have set the train times by my bowel movements. Once a day, regular as clockwork. But by day three, I am visiting the bathroom so regularly the children start to comment. And make fun of me.
    I go to Bupa to get re-tested, hoping that all the avocado and prunes were not consumed in vain. The results are unequivocal — I didn’t get any healthier. In fact I gained 2lb, climbing to 11st 8lb, my waist size increased by well over an inch, my body fat went up from 14.6 per cent to 15.9 per cent. “Maybe it was all that fibre you were eating,” the nurse suggested.

    Even my cholesterol measures slightly worsened with my HDL (“good” cholesterol) falling from 1.47 to 1.27. I am not suggesting that eating ten portions of fruit and veg is a bad idea. A study based on two million people is far more reliable than my one-week experiment. But, for me, hitting ten a day was expensive, tiring and involved, well, just an awful lot of food. ”

    • Any changes in dietary pattern are likely to result in changes in weight to start with. This can be due to water retention and also changes in your gut microbiota (which is likely to be growing with good bacteria). And you may have experienced some bloating because of this sudden rise in fibre intake, which is utilized by your gut microflora to create healthy short-chain fats. Fibre is also non-digestible, so it cannot in any way contribute to your digestible calorie intake.

      I question whether you actually balance your diet. Adding 10 pieces of fruit rather than substituting for other components of your diet will obviously make you gain weight because.

      Also “These studies are about health inequalities, not phytonutrients!” – the health inequality being the inability to get access to fruit and vegetables which offer the phytonutrients. Your closing statement is highly contradictory. It’s well known that there are health inequalities between the wealthy educated and the less fortunate of us. You’ve just pointed out yourself that the inequality in health is the inability to afford HEALTHY fruit and veg.

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