‘No thanks’ to corn and millet – there are better things out there

This column is written by Stig Bengmark – Professor Emeritus, scientist, lecturer and writer. Read more of Stig Bengmark’s columns here.

Of all the plants, corn is probably the one plant breeders have ruined the most. It’s also the plant most often ruined by genetic modification.

Once upon a time, corn was very small and contained a lot more of a lot of different nutrients than today’s ‘overbred’ corn. As usual, it was greed and the need for high yields that pushed this development forward to create the product we have now. If you ask me, corn is unsuitable for human consumption nowadays. I’d rather see it not even being used as animal feed – not least for environmental reasons. Every year huge areas of rainforest are destroyed to meet the need for corn as animal food, most of all for beef and dairy production.

Global production of corn is already widespread and it’s expected to continue growing at the same rapid pace in the coming years – at great cost to the environment. A drastic reduction in demand for meat and dairy products is actually the only thing that can stop this development.

Empty calories – nothing else!

Corn flour is just empty calories, like rice flour and potato flour – ‘junk flour’ – that we should all be happy to avoid. These types of flour all have unacceptably high GI:

Corn and corn products:
Corn flour 97, cornbread 92, cornflakes 121, corn chips/nachos 105, popcorn 79

Rice and rice products:
Rice cakes 117, rice noodles 131, quick cook rice 128, wholegrain rice 81, rice puffs 132

Potato products:
Crisps 77, mashed potato 118, potato flour 110

Unexpectedly, and to my great disappointment, there’s a lot of evidence suggesting there’s another cereal which should also be avoided, a cereal that lots of people unfortunately think of as nutritious: millet. The various worries with millet are:

  • It has a comparatively high GI – 101.
  • it contains a lot of saponins, known for increasing gut leakage and thereby the gut’s permeability towards toxins, for example, bacterial toxins such as endotoxin, and even residues of as well as whole bacteria.
  • It is rich in phytic acid/phytate – a substance known for binding useful minerals such as iron, calcium, zinc and magnesium – thereby reducing the body’s ability to absorb important minerals.
  • Another disadvantage which has been indicated is that millet has a very low amount of the essential mineral, iodine.

Corn – the worst of the worst

Corn is especially high in calories and often has large amounts of sugar added. A study of the calorie content of the popcorn in London’s numerous cinemas showed that only one of the cones or bags contained less than 1000 calories – i.e. an amount corresponding to at least half of the recommended daily caloric intake for a fifteen-year-old, as an example. The amount of sugar that’s often added actually doesn’t just increase the amount of calories but also contributes to the corn’s ability to cause increased inflammation in the body. Unfortunately, it’s also the case that popcorn isn’t just eaten by kids and adults on occasional cinema visits anymore, but actually quite regularly at home on the couch, watching TV – in many families it’s a much-loved element of their lives.

Corn is rich in the proteotoxin zein – more widely known as an ingredient used in plastic production

But it’s not the calorie content that makes corn such a villain – a lot of other foods share that property. What makes corn such a villain is that it contains a gluten- and casein-like proteotoxin, called zein. Zein is relatively unknown in health circles, but rather better known in the plastics industry. Zein is used, among other things, for the manufacture of various plastic products such as for coatings to prevent leakage in paper cups, to seal fabrics, for the manufacture of buttons and, just like gluten was in the past, for making adhesives.

In the human diet, zein has been shown to have a catastrophic influence on the activation of neurotransmitters, especially serotonin and melatonin and in fact also epinephrine and dopamine – all of them grouped under the term monoamines. Zein blocks the storage of the essential amino acid tryptophan in the body’s cells, especially in the brain cells – an essential amino acid is a substance that the body cannot produce itself, but which has to be supplied by your diet.

Linseeds, buckwheat, bananas, bitter cherries, and dark chocolate, among others, contain lots of tryptophan. It is widely known that in order for tryptophan to function optimally in the body, it also requires a rich supply of minerals like magnesium and vitamins like vitamin B6, for example. Sources of these include:


Monoamines such as serotonin and melatonin are of maximum importance for well-being

Serotonin – ‘the neurotransmitter of the calm soul’ – and melatonin – ‘the neurotransmitter of the circadian rhythm and sleep’ – among others, are created in the brain. It is well known that with several neuropsychiatric conditions, activation of these monoamines is far less than sufficient.

A very interesting study on animals shows that storage of the important substance, tryptophan, in the cells is greatly reduced by various proteotoxins: very strongly by zein, markedly by gluten (wheat, rye and barley) and casein (dairy products) but only negligibly by lactalbumin. Intake of plant proteins, however, improves this, albeit quite negligibly. A decrease in the availability of tryptophan in the brain is always accompanied by corresponding reductions in the synthesis/activation of the ‘vital’ neurotransmitters.

Inadequate monoamine function has been observed in several different neuropsychiatric conditions, for example

Lack of or insufficient balance of monoamines – especially in the brain – is actually well known in a number of neuropsychiatric diseases such as depression, ADHD, schizophrenia, Parkinson’s disease, and others – diseases that are also strongly associated with poor intestinal function (caused by poor eating habits) and poor absorption of a variety of substances such as vitamin D, vitamin K and tryptophan. My hope is that, in the future, reconditioning the gut flora with my synbiotics will contribute to increased release of important substances such as magnesium, various vitamins and especially tryptophan, thereby significantly improving the situation.

I’m convinced that we all feel good when we avoid corn, corn products and also, surely, millet. This should especially apply to those with neuropsychiatric diseases, and perhaps most especially to those with neuro-developmental disorders. Amphetamines, which are often used in the treatment of ADHD, have a molecular structure that’s actually very similar to tryptophan – it maybe be that it’s as a tryptophan replacement that it has its effects.

The nutrition is in the husk

The ratio of husk to meal being high is important – it’s mainly in the husk that all the nutrients are found. The meal is mostly empty calories, and we want as little of that as possible.  In my kitchen that I share with Marianne, things like corn, millet and rice are ‘barred’. Also excluded are gluten-heavy and over-processed rye, wheat and barley. Instead, we’ve been using a lot of quinoa and buckwheat, among others, for a long time. But unfortunately, we’re also seeing evidence of plant breeding with these – quinoa especially has become increasingly ‘mealy’ over the years. Now, the grains of our ancestors are marching forward in leaps and bounds – the ADT consortium of Amaranth, Durra, and Teff – primordial power! We humans (homo sapiens) came from Africa originally, and now, just a few thousand years later, the ancestral grains of our ancestors are also coming to us.

Dear plant breeder, we know that you’ve already cast your shadow on these cereals, but we beg you: for the sake of our health, leave them alone.

• Choi S et al Physiol Needs 2009;98:156-162

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