Just an attempt to contribute to the discussion. A lot of the confusion seems to stem from what 'low carb' entails. For me it means: do not add sugar, do not eat 'refined' grains, no soft drinks (who needs them anyway?). Just eat wholemeal products (eg pasta, brown rice etc), fruit (which contains the dreaded fructose but also fibers which neutralize the damage). Even Robert Lustig, an MD who made a comprehensive study of the damaging effects of fructose, said that fructose in fruits/veggies does not matter so much, because a) the concentration is low and b) fruits contain the 'antidote' to fructose, ie fibre. Fibre slows down the release of sugars to the blood, so eating fruit does not cause a glucose spike and therefore no insulin spike either with all the damaging effects this may have.
Cutting out carbs from the diet completely (which would be very difficult and perhaps even impossible) might cause a shortage of certain minerals and vitamins, because it would mean that you'd have to stop eating fruits and veggies, which would not be healthy. So strictly speaking saying that restricting the carb content of your diet might lead to malnutrition is true, but it certainly isn't the whole truth.
Last year I followed a course at Leiden University called 'current developments in medicine', and all the lecturers from the lung specialist to the cardiologist to the internist stressed the beneficial effects of reducing calories, losing weight and reducing the amount of carbohydrates in the diet. All of them had the metabolic syndrome as their theme and how to prevent it or, in some cases, reverse it.