So, to remind you all that the aim of this blog is to attempt to show that there’s no need for any carbs at all in the human diet, which naturally means no fruit and vegetables, and therefore that the old 5-a-day guideline is quite simply misguided and unnecessary. One of my concerns about the downsides of eating a diet that includes carbs is mental health. So I’ll throw out a few basic quickfire points in this post to give you all something to chew on. Food for thought.
We know that the standard western diet (should that be US/UK diet? What nations are more obese than the UK/US?) causes lots of damage: inflammation; oxidation; insulin resistance; hormonal problems; micronutrient deficiencies.
Now then, just as these issues can affect the internal organs and systems, so can they affect the brain. As Dr Georgia Edes, practising psychiatrist and low-carb guru points out, studies invariably show that the head is part of the body. Why wouldn’t the sort of whole-body physical ill-health that results from poor nutrition – metabolic syndrome, for example – not affect the functioning of the brain, and hence mental health too? Panic attacks, depression (the number one cause of disability in the world at the moment), obsessive behaviour, dementia – could these be mediated by diet?
For example, our neurotransmitters need fat to make them effectively neurotransmit. Not cellulose or vitamin C or anything else plant-derived. The brain is 60% saturated fat, and a lot of our cognitive function is down to the presence of the magical, wonderful substance that is cholesterol. Low cholesterol levels cause low serotonin levels which in turn cause depression. And violent behaviour. And suicide, even. One study compared the psychological effects of high-fat and low-fat diets on the same ‘psychologically robust’ cohort, and found that mental health markers were always better on the high-fat diet.
A common symptom of low serotonin (caused by low levels of tryptophan, the result of not enough animal protein and fat) is obsessive behaviour. Common examples are hand-washing (50 times a day, for example) and, especially in teenage girls, obsessive calorie counting and perceived body defects (serotonin underpins our sense of self-worth). On that point, anorexia clinics typically report that around 50% of their patients are vegetarian.
The next thing about neurotransmitters is that they are built out of protein. For millions of years we’ve built them out of animal protein, of course. So nowadays, when the only source for some people is poor-quality plant protein from legumes, imagine (if your brain lets you) what poor-quality neurotransmission takes place. Lierre Keith, author of ‘The Vegetarian Myth’, tells the story of how someone she knew asked her over for dinner, and told her to ring the night before, which she did. The friend struggled to remember Keith’s name, or having made the invitation, but eventually confirmed the dinner date. The next evening when Keith turned up there was no dinner, just a cup of tea with soy milk – ‘I’m a vegan’ – she said. After a silence, the friend suddenly realised why she’d invited her over: ‘You know about soy. Does soy cause memory problems?’
The brain (and the heart) run 25% more efficiently on ketones than on sugar, it has been estimated. Eating fruit and veg, and of course grains and sugary foods, is bound to prevent ketone production and force the brain to run on circulating glycogen. A brain fed exclusively on sugar will not fare any better than any other organ fed on sugar. Alzheimer’s disease is now often referred to as ‘type 3 diabetes‘. Basically, a standard western diet, replete with processed carbs and lots of vegetable oil, causes insulin resistance, and insulin resistance appears to be a driving force, to quote Dr Edes, behind Alzheimer’s.
Anecdotally, too, a diet that eliminates carbs and stocks up on animal fat and protein is the best diet for good mental health: many, many people report depression leaving them as they turn to a high-animal -fat diet, many. many people report heightened alertness and greater clarity on a carb-free diet, and so on and so on.
We simply cannot expect fruit, or vegetables, or grains, to make a positive contribution to brain health and our mental wellbeing. They don’t, not in the short term and especially not in the long term, which is all the more reason to avoid them completely. They have no benefits, and lots of downsides. Given that we know, as a biological fact, that humans have no dietary requirement for carbs, it makes even more sense to not eat any in the light of the above – every bit of sugar that goes in is potentially harmful for the brain as well as the body.
To see Dr Edes in action, discussing mental health and diet, please watch this: https://www.youtube.com/watch?v=TXlVfwJ6RQU
And have some brainbutter.