Food without religion
Few subjects create as much certainty, confusion and moral superiority as food.
One person has removed carbohydrates from his life and speaks of bread as if it were an illegal drug. Another follows a plant-based diet and looks at butter with the expression usually reserved for organised crime. A third counts every calorie, while a fourth insists that calories do not matter at all.
Meanwhile, most of us are simply trying to eat reasonably well, remain healthy and avoid acquiring a waistline that enters the room before we do.
Nutrition matters. It affects body weight, blood sugar, blood lipids, blood pressure, cardiovascular health, muscle mass and general well-being. But food is also culture, pleasure, habit and companionship. Any sensible discussion of diet must therefore include both physiology and ordinary life.
The Uncomfortable Importance of Calories
Body weight is strongly influenced by calorie balance. Over time, if we regularly consume more calories than we use, the excess has to go somewhere. The body is remarkably efficient at storing it, usually in the very place where we would least like to admire that efficiency.
This does not mean that weight regulation is simple. Appetite, sleep, stress, hormones, age, medication, genetics, muscle mass, insulin sensitivity and the type of food we eat all influence the equation.
A calorie from protein does not affect appetite and metabolism in exactly the same way as a calorie from sugar or fat. Nevertheless, calories do not cease to matter merely because we have chosen a fashionable name for the diet.
Must We Count Every Calorie?
Calorie counting can be useful, particularly for a limited period. It teaches us how many calories different foods contain and how easily seemingly small snacks accumulate.
But doing it indefinitely can become exhausting. A person should be able to eat dinner without conducting a small audit of every potato.
For many people, it is easier to estimate the amounts of the three main macronutrients: carbohydrates, protein and fat.
Protein and carbohydrates provide approximately four calories per gram, while fat provides approximately nine. Alcohol contributes about seven calories per gram, despite its frequent attempt to present itself as a beverage rather than a nutrient.
Some practical approaches suggest limiting carbohydrates to about one gram per pound of ideal body weight and aiming for roughly one gram of protein per pound. For someone whose ideal weight is around 150 pounds, or 68 kilograms, that would mean no more than approximately 150 grams of carbohydrates and a similar amount of protein each day.
This is not a universal prescription. It is a relatively high protein target, and the appropriate intake depends on body size, age, activity level, muscle mass, health and kidney function. But the method can offer a simpler framework than counting every individual calorie.
Of course, counting macronutrients is still a form of calorie counting. It simply allows the accountant to wear more comfortable clothes.
Carbohydrates and the Glycaemic Index
Carbohydrates vary greatly in how quickly they are digested and absorbed. The glycaemic index, or GI, ranks carbohydrate-containing foods according to how rapidly they raise blood glucose.
Foods with a high GI tend to produce a faster rise in blood sugar and a stronger insulin response. Examples may include white bread, cornflakes, waffles, doughnuts, baked potatoes and many highly processed snacks.
Foods with a moderate GI include many kinds of fruit, oatmeal, rice, sweet potatoes, corn and some forms of pasta.
Lower-GI foods include lentils, barley, many vegetables, apples, oranges and minimally processed wholegrain products.
These categories are not absolute. Cooking methods, food processing, fibre, fat and protein all affect how rapidly carbohydrate is absorbed. A baked potato and a cooled potato are not metabolically identical, and ice cream may produce a slower glucose rise than expected because its fat content delays absorption. That does not turn it into broccoli.
The glycaemic index is therefore useful, but it does not tell the whole story. Portion size matters, as does the total amount of carbohydrate. This is why the concept of glycaemic load may sometimes be more informative.
Wholegrain foods generally produce a gentler response because their fibre slows digestion. Fibre also supports bowel function, satiety and the gut microbiome.
Low-Carbohydrate Diets
Low-carbohydrate diets reduce bread, pasta, rice, potatoes, sweets and other concentrated sources of carbohydrate. Many allow generous amounts of meat, fish, eggs, cheese, nuts, vegetables and fats.
LCHF—low carbohydrate, high fat—is one of the better-known versions. Some forms permit substantial quantities of saturated fat, including butter, cream and fatty meat. That aspect has understandably attracted criticism.
Other low-carbohydrate approaches include the Atkins diet, the South Beach diet and the Paleo diet. They differ in detail, particularly in their attitudes towards fat, dairy products, processed food and whole grains.
The Zone diet is not strictly a low-carbohydrate diet, but it recommends a lower proportion of carbohydrate than many traditional guidelines: approximately 40 per cent carbohydrate, 30 per cent fat and 30 per cent protein.
Low-carbohydrate diets can be effective for weight reduction, particularly in people with overweight, obesity, insulin resistance or type 2 diabetes. They often reduce appetite, and the rapid initial fall in weight can be encouraging, although some of that early reduction is water.
However, low carbohydrate should not mean low nutrition. A diet consisting mainly of bacon, butter and enthusiasm is not automatically healthy.
Vegetables, fibre, good-quality fats and adequate protein still matter. If calorie intake becomes too low and protein intake is inadequate, muscle may be lost along with fat. That is rarely a good bargain, particularly with increasing age.
Fat Is Not One Substance
Food does not contain exclusively saturated or exclusively unsaturated fat. Most fats are mixtures, although the proportions differ.
Foods rich in unsaturated fats are often liquid at room temperature, as with olive oil. Foods containing more saturated fat, such as butter, are more likely to be solid.
Unsaturated fats found in olive oil, rapeseed oil, nuts, seeds, avocados and fish generally fit well within a heart-healthy diet.
Saturated fat deserves moderation rather than hysteria. Its health effects depend partly on what replaces it. Replacing saturated fat with unsaturated fat is usually beneficial. Replacing it with refined starch and sugar may achieve very little.
Industrial trans fats are a different matter. They have adverse effects on blood lipids and cardiovascular risk and should be avoided as far as possible. They have traditionally been found in some margarines, baked goods, sweets, snacks and deep-fried processed foods, although regulation has reduced their use in many countries.
Protein Becomes More Important With Age
Protein helps preserve and rebuild muscle. This becomes increasingly important as we grow older because muscle mass and strength naturally decline unless we actively defend them.
Older adults may therefore need more protein than they imagine, especially when losing weight or doing resistance training.
Protein should usually be distributed across the day rather than concentrated entirely in one evening meal. Fish, eggs, dairy products, poultry, lean meat, beans, lentils and other legumes can all contribute.
Adequate protein does not mean that every meal must resemble a Viking feast. It means supplying the body with enough raw material to maintain muscle, function and recovery.
The Mediterranean Diet
The Mediterranean diet has some of the strongest evidence for cardiovascular and metabolic health.
Its foundation consists of vegetables, fruit, legumes, whole grains, nuts, seeds, olive oil and herbs. Fish and seafood are eaten regularly, while yoghurt, cheese, eggs and poultry are consumed in moderate amounts. Red and processed meat are limited.
The diet is relatively high in fat, but much of that fat comes from olive oil, nuts, seeds and fish rather than heavily processed foods.
Herbs, garlic, basil, fennel, lemon and other seasonings are commonly used instead of relying only on salt. Fruit is often the main dessert, although pleasure has not been formally outlawed. Wine is often mentioned in descriptions of the Mediterranean diet. A glass with a good meal can certainly be enjoyable, but wine is not an essential food group – and a bottle of red does not become health food merely because it is served beside a bowl of olives.
Wine is often mentioned in descriptions of the Mediterranean diet. A glass with a good meal can certainly be enjoyable, but wine is not an essential food group – and a bottle of red does not become health food merely because it is served beside a bowl of olives.
The Mediterranean pattern is also about how meals are eaten. Food is often prepared at home and shared with family or friends. This may be difficult to reduce to a laboratory variable, but it is probably not irrelevant.
A healthy diet eaten slowly in good company may affect us differently from the same food consumed while reading alarming emails over the kitchen sink.
The Atlantic Diet
The Atlantic diet comes mainly from north-western Spain and Portugal. It shares many features with the Mediterranean pattern but reflects a cooler climate and different local traditions.
It emphasises fresh, seasonal and locally produced food, including fish, seafood, legumes, vegetables, fruit, potatoes, wholegrain bread, dairy products and some meat. Olive oil is commonly used.
Compared with the Mediterranean diet, it may include more potatoes, cabbage, cauliflower, turnips, dairy products and red meat, although the meat is often relatively lean. Slow-cooked dishes, soups and stews are common.
The Atlantic diet is attractive because it is based on recognisable food rather than industrial products designed by a committee and advertised by an athlete who has probably never eaten them.
The Nordic Diet
The Nordic diet follows similar principles using foods suited to northern climates.
It emphasises whole grains, especially rye, oats and barley; berries and other fruit; root vegetables; cabbage; legumes; nuts; seeds; rapeseed oil; fish; and low-fat fermented dairy products such as skyr and yoghurt.
Fatty fish such as salmon, herring, mackerel and sardines provide omega-3 fatty acids. Processed meat, added sugar, heavily salted food and sweet drinks are limited.
The Nordic diet may not have been studied as extensively as the Mediterranean diet, but it offers a sensible framework using local and seasonal ingredients.
We do not all need to pretend that we live beside an olive grove. Rye bread, fish, cabbage, berries and skyr can also form a respectable meal.
Intermittent Fasting
Intermittent fasting focuses mainly on when food is eaten rather than precisely what is eaten.
Common methods include restricting meals to an eight- or ten-hour period each day or reducing food intake substantially on selected days.
It can help some people reduce their overall calorie intake without constant counting. It may also improve insulin sensitivity and other metabolic markers in certain individuals.
But fasting is not metabolic magic. If the eating window becomes an eight-hour festival of pastries, crisps and large meals, the result may disappoint.
It is also unsuitable for some people, including those with certain medical conditions, a history of eating disorders or medications that can cause hypoglycaemia. Anyone in those groups should seek professional advice.
Diets Work Only When People Can Live With Them
Almost any structured diet can produce short-term weight loss if it creates a calorie deficit. The more important question is whether a person can follow it for months and years.
A diet that requires constant hunger, social isolation and carrying emergency boiled eggs to every family gathering is unlikely to last.
The best eating pattern is usually one that:
provides enough protein and fibre;
contains plenty of minimally processed food;
limits sugar, refined starch and highly processed products;
includes fats mainly from fish, olive or rapeseed oil, nuts and seeds;
controls portions without creating constant misery;
fits the person’s health, culture, finances and daily life;
and can be continued after the first burst of enthusiasm has faded.
A Voice Worth Reading
Axel F. Sigurdsson is one of Iceland’s best-known cardiologists and one of the people I most respect for his ability to explain metabolism, nutrition and cardiovascular health.
Years ago, he ran an excellent Icelandic-language website called mataræði.is. The site has not been maintained, but he now writes in English at Doc’s Opinion: https://www.docsopinion.com/
Axel writes for both general readers and those with a medical or scientific background. He has the valuable ability to explain complicated physiology without oversimplifying it and to discuss diet without turning it into religion.
Readers who want to explore metabolism, heart health and nutrition in greater depth will find much of value in his writing.
A Practical Middle Ground
For many people, the most realistic approach is not to join a nutritional tribe but to borrow sensible ideas from several traditions.
That may mean:
eating enough protein to preserve muscle;
choosing vegetables, legumes and minimally processed foods regularly;
favouring fish, olive oil, rapeseed oil, nuts and seeds;
reducing sugar, white flour, sweets and heavily processed snacks;
adjusting carbohydrate intake to activity, weight and metabolic health;
being aware of portion size;
allowing occasional pleasure without declaring the entire week ruined;
and combining dietary change with physical activity, sleep and stress management.
Perfection is neither necessary nor particularly sociable.
A person who eats well most of the time will not be destroyed by a piece of cake. The greater danger is often the thought that one piece of cake has already ruined everything, so the rest of the cake may as well be prevented from becoming lonely.
Food Without Religion
For me, the most attractive combination includes some restriction of refined carbohydrates, enough protein to preserve muscle and many of the foods and principles found in Mediterranean and Atlantic eating patterns.
That does not make it the only correct answer.
Food should support life rather than occupy all of it.
We need to understand what we eat, but we should not have to calculate the nutritional history of every carrot before placing it on the plate.
Theory can take us only so far.
Eventually, someone has to open the refrigerator and decide what to eat.