Grain Brain is a book all about our grain diet, and how eating lots of grains is a bad idea for us. Dr David Perlmutter is a doctor and a nutritionist. He not only knows his stuff; he also explains the issues well, in clear prose that includes interesting details and a good balance between the science and the practical consequences.

In the book, Dr Perlmutter explains that we are not built to consume grains. This is hardly surprising, since the practice of growing large amounts of grain to feed a human population is only a very recent development, at least in terms of the human species. Before we started growing grains, in around 4,000 BC, we existed on a hunter-gatherer diet. This consisted of very fresh meat, fresh fish, nuts, leafy greens and seasonal berries. We would have eaten some carbohydrates, in the form of tubers, but we would have eaten hardly any grasses, including wheat, rye, barley and rice. Our digestive systems are therefore set up to digest a non-grain diet. Since civilisation began, this sudden influx of large amounts of starch into our diet, which is quickly broken down into sugars in the gut, has caused our bodies serious problems. If we add in the fact that we’re consuming actual sugars, especially in the form of concentrated fruit sugars, then it’s even worse for our bodies.

The digestive mechanics of this problem are well known. If we eat meals heavy with grains and fruit sugars, this will create a rapid increase in the amount of sugar in our blood. Our body but then work hard to remove those sugars from our blood system. It does this by pumping out insulin, which shepherds the sugar into our cells. But our cells can only take in so much sugar. Once they’re full, they begin to close the gates to more sugar coming in. As a result, even though our pancreas has pumped out lots of insulin to get sugar into cells, the cell-doors are closed. The sugar therefore doesn’t leave our blood system. This is bad for our body because sugar is a toxin. As a result, people get diabetes, blood pressure problems, heart problems, circulation problems etc e

Many people already know about sugar’s effect on the body, but Dr Perlmutter also points out that high carbohydrate and sugar levels can cause another serious problem; inflammation in the brain. This, in turn, can cause long-term cognitive damage. This grain-sugar-brain link touches upon another hidden side to eating grains. Gluten, which is present in wheat and other grains, breaks down in the gut to form peptides and these have a strong effect on our brains. They give us a warm, fuzzy feeling, because they bind to opiate-type receptors in our brain. In this way, our food can be a drug. Sometimes, a meal can be many drugs at once. For example, a pizza and coke is gluten-peptides (opiate analogues), caffeine (psychoactive), spices (psychoactive) and sugar (dopamine high, addictive properties). Even the cheese is psychoactive because it is a concentrated source of casein, which is also psychoactive.

I found Dr Perlmutter’s book to be a fascinating and sobering read. I’ve taken on board his recommendations and for a month, I switched to his recommended diet. I soon found that I wasn’t drowsy after meals, and I didn’t get peckish anything like as easily as I had before. I also found that when I did have carbohydrates, such as pasta or potatoes, I did get a headache shortly afterwards, which persisted for several hours.

For anyone that worries that they might gain weight with a diet high in fats, Dr Perlmutter explains in great detail that people don’t get fat on a fat and protein diet, they get fat on a sugar and carbohydrates diet, because their body has to turn the sugars into fats and store them to get them out of the bloodstream. By comparison, once you’re on a fat and protein diet, the body burns the fats in its cells naturally and sends you signals that you’re full and okay for ages. This form of digestion is known as ketosis, or a ketosis diet. It is also recommended to prevent certain cancers, since cancer cells can’t burn fats, they can only burn sugars.

Here’s my summary of Dr Perlmutter’s recommended diet. Check his book for confirmation, extra details and recipes:

Antioxidant boosters:

These boost the body’s own antioxidant system, leading to better body and brain health.

Turmeric (350mg twice daily), Green tea extract, Milk Thistle, DHA (often from fish oils: 1g daily), Broccoli, Ashwagandha, Coffee, Vitamin D.

Healthy oils:

Coconut oil (1tsp daily), Olive oil, olives, sesame oil, almond milk, avocados, nuts and nut butters (remembering that peanut is a ‘groundnut’ or tuber), cheese, pasture fed butter, sesame seeds, sunflower seeds, chia seeds.

Healthy vegetables:

Peppers, cucumber, courgette, leafy greens and lettuces, spinach, cabbage, onions, mushrooms, cauliflower, sprouts, artichokes, green beans, celery, bok choi, watercress, asparagus, garlic, leek, spring onions, ginger, parsley, water chestnuts.

Healthy proteins (for a piscetarian):

Eggs, wild fish (salmon, black cod, herring, trout, sardines), shellfish and mollusks (shrimp, crab, clams, mussels, oysters), hummus.

Foods to have in moderation (once in a while):

Cottage cheese, cow’s milk, beans, lentils, peas, rice, pure oats, very dark chocolate, berries.

Foods to have very sparingly:

Melons, apricots, papayas, mangos, prunes, pineapple.

One more point to add; it’s true that the food industry has been persuading people that diets high in fats are dangerous, and also that high cholesterol is dangerous. Dr Perlmutter explains in great detail that cholesterol is actually a vital component of our body and is needed to transfer fats into our brains, which are mostly fat. As reported in his book, studies have shown that people with low cholesterol, including those taking statins, have a much higher risk of Alzheimers and other cognitive degeneration illnesses. Damaged cholesterol, oxidised by sugar and free radicals, is dangerous to the body but the fault lies with the carbohydrate diet, not the cholesterol itself.

Overall, I definitely recommend Dr Perlmutter’s book.