Comments on: Wholegrains: the whole story?

By: Bill Shrapnel

Bill Shrapnel — Wed, 13 Jun 2012 23:56:14 +0000

Hello Nick. Good point, but now that grains are so much a part of the human diet I guess the question for nutritionists is what grain foods should be recommended. As with all carbohydrate-rich foods, the answer is not as simple as it would appear. Carbohydrate quality is a complex concept (more on this soon). Regards, Bill

By: Nick

Nick — Wed, 13 Jun 2012 10:55:58 +0000

A very good read and an excellent insightful article. I enjoyed it very much. I’d have liked to have seen some example figures enabling nutrient comparison to re-enforce your points. Grains, whether whole or otherwise require substantial processing to make them edible and for the most part of human evolution were simple not available. How is it they have become the mainstay of a healthy diet?

By: Bill Shrapnel

Bill Shrapnel — Tue, 15 May 2012 23:40:54 +0000

Hi Jemma.

All cereals tend to have low nutrient densities i.e. they provide relatively few nutrients per kilojoule. Among the cereals, rice has the lowest nutrient density. White rice is particularly low but brown rice is not much better. That’s why I suggest that nutritionists need to be a bit cautious about arguing that wholegrain equals good.

I agree that the GI evidence has improved in recent years (I’ll discuss this next week) and I think it should be considered when we advise people on carbohydrate-rich foods. But I don’t think GI or wholegrains provides the whole answer. Carbohydrate quality is complicated and I suggest that fibre/wholegrain, GI and nutrient density are all relevant. However, it would be a mistake to pick just one of these (say wholegrain) and suggest that’s the whole answer. Regards, Bill

By: Jemma O'Hanlon APD

Jemma O'Hanlon APD — Tue, 15 May 2012 00:50:43 +0000

Hi Bill,

Thanks for an informative article. Could you elaborate on your rating of brown rice as a nutrient-poor food? This may come across as quite confusing to an every-day consumer.

Do you think as dietitians we should we be recommending low GI foods over wholegrain foods? It certainly seems that there is more quality evidence for low GI, but I also think there is a place for wholegrains, even if the evidence is not quite there.

Thanks

Jemma

By: Bill Shrapnel

Bill Shrapnel — Mon, 14 May 2012 09:49:21 +0000

Hello Robert. Firstly, there is no consensus on how nutrient density should be calculated. I suggest you read Drewnowski and Fulgoni (2008) to get a feel for the way this issue has been approached in the literature. In some work that a colleague and I recently completed we developed a nutrient density score based on six principles that Drewnowski and Fulgoni recommend:
1. a focus on nutrients with accepted nutritional roles i.e. those with Nutrient Reference Values
2. assessment of nutrient density within food groups
3. identification of index (or distinguishing) nutrients for each food group
4. development of an algorithm for nutrient density
5. assessment against recognised standards, in this case the Nutrient Reference Values, and
6. calculations of nutrient density be based on a fixed amount of energy for each food.

Some models of nutrient density include negative terms for fat or sugar, but this doesn’t make sense to me. If fat and sugar dilute nutrients then this should be expressed through the model, as calculations are based on a fixed amount of dietary energy. Regards, Bill.

Reference: Drewnowski A, Fulgoni V. Nutrient profiling of foods: creating a nutrient-rich food index. Nutr Rev 2008; 66: 23-39.
.

By: Robert

Robert — Mon, 14 May 2012 08:57:16 +0000

Bill, thank you for the very informative article and the discussion on the results of the intervention studies.
Could you reveal what measure you use for overall nutrient density? A quick search showed that some people have developed and used measures of aggregate nutrient density (e.g. “ANDI”). On this scale, some whole grains have respectable scores, though not even coming close to the high nutrient density green vegetables.
My own hand calculations indicate that oats are more zinc-dense (zinc per unit energy) than dairy & cooked eggs- foods commonly thought to be nutrient powerhouses.

By: Duncan Hunter

Duncan Hunter — Mon, 14 May 2012 03:20:20 +0000

Great read and interesting after reading the grains and legumes nutrition council mail out. I love the comment about brown rice. Thanks again.

By: Leah

Leah — Sun, 13 May 2012 21:53:51 +0000

Thank you for taking a more real view on foods, and not allowing commercial or scientific community norms influence your writing. I have been thinking these same things for some time, and it frustrates me that the mainstream is so reluctant to move from engrained held beliefs that are grandfathered by use.