Those who have been around long enough in the obesity research area, typically despair of the public approach to ‘diets’ – low carbs, low fat, high protein – as a long-term solution for weight loss.

All come with ‘evidence’ that they work – at least within the limited sample and time span with which they’re tested. And all come with front-page publicity.

So it’s sobering to see the meta-analysis in the September issue of JAMA that showed that when compared head-to-head, all the major ‘name’ diets work – at least a little, and at least for a while – with little between them, leading the researchers to conclude that the best diet for any one particular individual is the one that person can stick to!

And surprisingly, not many can be stuck to – at least for a lifetime, which is what is required for long-term success.

Recent findings on ‘fat memory’ and the gut microbiome, show us why this is so, and why any diet that works, has to be one that can be adhered to for a lifetime.

Changes occur physiologically with weight gain that make the body want to defend that gain, even after there has been a significant loss. Changes in the microbial balance in the gut, not only with weight gain, but with the changes in diet and exercise that may, but don’t always necessarily lead to weight gain, remain for some time after weight loss.

A ‘leaky gut’ for example, leads to greater ‘food harvesting’ resulting in the body storing energy more efficiently. A kilojoule in an ex-obese individual, as measured in a test tube, might effectively become 2, or even 3 kilojoules once ingested into the obese or ex-obese body, making the physics-based energy-balance formula inaccurate, to say the least.

After experience with this, and failure to keep weight off, most people will quit that diet and move on to the next, with the hopes and enthusiasm that begin with the last diet– irrespective of its gimmicky bias.

So, what can be done if you want to help a patient who is genuinely determined to live more healthily and, in the process (perhaps) lose weight?

In the first instance you can avoid the word ‘diet’. It’s an acronym for a ‘Depressing’ ‘Inexcusable’ ‘Expenditure’ of ‘Time’. In theory it implies eating (and/or avoiding) and drinking set foods at set meals during the course of the day.

The reason this, and very restrictive diet plans don’t work, is that they don’t usually deal with the main problem – hunger. (Don’t get confused here with appetite. The latter is the learned drive to want to eat; it can be put off or postponed by being distracted. The former, hunger, is the biological drive to need to eat).

Hunger and sex are amongst humanity’s two strongest drives, as it should be because both guarantee survival of the species. (Incidentally, one can be used to test the genuiness of the other: If thoughts of sex for example are sufficient to override feelings of hunger, it’s most likely appetite and not genuine hunger that’s being felt).

A second approach for healthy eating is to follow Brazilian nutrition scientist Carlos Monteiro’s idea that ‘the issue is not food, nor nutrients, so much as processing’. He considers three food groupings: Group 1 are minimally processed whole and natural foods, such as plants, fruits, vegetables, roots and tubers.

Group 2 is made up of substances that are extracted from whole foods such as oils, fats, flours, pastas, starches and sugars, which aren’t usually consumed by themselves, but used in food preparation.

Group 3 are ultra-processed foods, usually made up from the raw materials from group 2 to make low nutrient dense processed products such as breads, cookies (biscuits), ice creams, chocolates, confectionery (candies, sweets), breakfast
cereals, cereal bars, chips (crisps) and savoury and also sweet snack products in general, and sugared and other soft drinks.

Monteiro’s simple approach is to eat more of group 1, less of group 2 and nil, or minimal of group 3.

This is confirmed through another recent approach based on an anti-inflammatory eating plan. Recent work has shown that there is a low grade, systemic, inflammatory reaction by the immune system to certain foods (generally Monteiro’s group 2 and 3 foods) suggesting that humans have not evolved with these types of foods, but a neutral or pro-inflammatory response to more natural, whole foods (Monteiro’s group 1).

It’s perhaps ironic that in the month that the JAMA meta-analysis was published, several other articles purportedly ‘proving’ the effectiveness of low carbohydrate over low fat diets – or vice versa – also hit the scientific press. Little wonder the public is confused. The bottom line however seems to be summed up in the JAMA analysis: “The best diet is the diet the patient can adhere to.”