I left off at the start of summer posing the question "fats - good or bad?" and explaining that the answer is not simple - it depends on the fat, the processing, our individual body etc.
I thought it would be worth posing the same question about carbohydrates.
'Carbohydrates' is the word that covers both starches (long chain carbohydrates) and sugars (short chain carbohydrates). We have been taught, certainly in the UK, over the last 40+ years that starchy carbohydrates are good for us. "Slow release energy" and "Keep you going" are phrases often associated with these. Breakfast cereal companies have made a big thing of it with 'keep hunger at bay until lunch' type messaging and claims of the health of whole-grains being big selling points. Sugars on the other hand have been vilified - we have been encouraged to have "sugar free" and look for the sugar content on labels.
So does this simplistic messaging stand up to scrutiny? - Probably not!
Looking initially at Breakfast, where in the UK most people major on purely carbohydrate loaded foods.... (see these blog articles for more)
There are some people (I have no empirical data on numbers but I'd be surprised if it was much above 10% of the population) who can eat 2 Weetabix or a bowl of Shreddies (both around 200 kcal or 1/10th of the recommended for a day when including the milk) and truly not feel hungry or grumpy or agitated or in need of a coffee until 4-5 hours later. ... For those people the "slow release energy" messaging seems to stand true, but for most of us the need for a mid morning snack - even if that is just coffee (with milk and/or sugar) tells us that our bodies do not feel that such a breakfast has been adequate. In some ways this may be due to the limited calories that such a breakfast gives - only 1/10th of our recommended daily - but the bigger problem for most people is not the hunger driving them to that mid morning snack but the loss of concentration and the grumpiness - and these are indicative of sugar crashing. The reason for this is that it doesn't matter how long the original carbohydrate chain is - it is all broken down into sugar by our digestion.
Similarly if we look at lunch - most of the UK population of working adults and children eat sandwiches for lunch - i have already looked at some of the issues with those in this blog article. The postprandial lunch slump is real for many and a problem for teachers and office companies alike with regard to productivity of students and workers. Again, this is due to the carbohydrate load - a sugar high followed by a sugar crash.
Of course - being very cynical about it - those companies who make the breakfast cereals also make a lot of the snack bars many are drawn to. They don't mind at all if you sugar crash mid morning and mid afternoon and need more of their products to get you through to dinner. But your body and your brain - they do mind. ... over time these constant highs and lows of sugar levels stress our bodies: They put strain on our pancreas and they create resistance to insulin leading to type 2 diabetes; they put strain on our immune system leaving it less time to clean up other toxins - and it is thought this is a mechanism for why high sugar (high carbohydrate) diets seem to increase the risks of dementia, cancers and inflammatory illnesses.
Having said all that - it is important to remember that carbohydrates at the right time are useful. We need their easy energy when we are working hard physically - so athletes often carb load before an event - and we need glucose, in small and steady quantities for brain function.... so those studying hard and those whose jobs require complex thought and concentration will also need to have adequate intake in appropriate formats.
And finally, as is becoming more clear day by day at present, for carbohydrates as for fats and proteins, the key is understanding your own body and your own metabolism and learning how tot read the signs.
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