Surprising findings show white bread is just as healthy as brown

Is white bread really any worse than brown? Photo / Getty

Cheap white bread is just as good for our health as whole wheat sourdough bread, a controversial study claims.

The findings - which surprised the researchers - analysed levels of nutrients in the blood of volunteers.

It also looked at levels of healthy gut bacteria over one week in both groups.

According to the Daily Mail, there was no difference between the two types of bread in terms of health effects.

Critics say that while the health benefits may be similar over a short time period, the study did not take into account people eat less higher-fibre bread.

In addition, the presence of the roughage may prove better for your health over a lifetime.

How was the study carried out?

Researchers at the Weizmann Institute in Israel gave a group of 20 healthy volunteers white bread for a week, and, after two weeks of no bread, artisanal whole wheat sourdough bread for a week.

For both types of bread, the participants ate enough to provide 25 per cent of their weekly calories.

Before and during the study, the scientists monitored a host of health effects.

These included the participants' glucose levels on waking, the levels of calcium, iron, and magnesium, fat and cholesterol levels and kidney and liver enzymes.

In addition they looked at markers that would indicate inflammation and tissue damage, as well as the bacterial make-up of their gut.

No clinically significant differences

Dr Eran Segal, one of the authors of the study said: "The initial finding, and this was very much contrary to our expectation, was that there were no clinically significant differences between the effects of these two types of bread on any of the parameters that we measured.

"We looked at a number of markers, and there was no measurable difference in the effect that this type of dietary intervention had."

What did they find?

The researchers found that in terms of blood sugar levels, some of the participants responded better to the white bread than the brown bread, and a roughly equal number responded to the wholegrain bread.

But the authors pointed out that one issue that the study did not address was that many people eat less high fibre bread, such as whole wheat sourdough.

Dr Avraham Levy said: "We know that because of its high fibre content, people generally eat less whole wheat bread.

"We didn't take into consideration how much you would eat based on how full you felt. So the story must go on.'

Duane Mellor, a dietician and spokesman for the British Dietetic Association said that the study looking at the body's responses after each meal over just one week was too short to assess bacterial changes in the gut.

He said: "For most people, whole grain bread, sour dough if you like the flavour, will provide more fibre which will reduce longer term diseases such as cancer, cardiovascular disease and possibly type 2 diabetes."

No measurable effect on health

Professor Susan Jebb, Professor of Diet and Population Health, University of Oxford, said: "It may be that this is too small a group to detect potentially small differences but the fact remains that there was no measurable effect on health."

She added that the design of the experiment made 'it very difficult to draw any robust conclusions specifically about bread from this analysis'.

Dr Elizabeth Lund said: "Although the results of this study are interesting, it should be noted that they are not conclusive and the study itself is small (only 20 participants).

She added: "The intervention was very short at only one week for each type of bread, especially compared to previous studies that have showed a benefit of whole grains in the control of blood glucose. It is therefore not surprising that no effect in eating the different types of bread was observed."