When people decide to make a change to their diet often it’s because they want to feel better, so they start trying to make healthier choices. But with one person telling you one diet is the “best”, and another saying, no, this one is the “healthiest”, and yet another saying you “must” eat this way, how are you supposed to know where to start?
There are so many factors which affect our health. To isolate cause and effect from single food items (or single nutrients) is almost impossible and overly reductionist! Correlation ≠ causation, and just because one thing is associated with another it doesn’t mean we can say that is the cause. You may start to notice a theme across my posts on here, which is a lack of black and white absolute answers. The study of nutrition features so much nuance.
When it comes to healthy eating, it’s your overall dietary pattern that’s important and should be what to focus on, rather than single nutrients. While some areas of nutrition may be debated (rightly or wrongly), others we have a wide body of literature on to be more confident in recommendations. These are where I’d start, when looking at the foundations of setting up a balanced diet.
This is about the diversity of the sources of plant foods as a whole that you consume, not just vegetables. You may have heard the target getting 30 different plant sources a week? Well, if not, that came from a study which found that people who consumed a larger number of unique plant species (>30, compared with 10> a week) were associated with having a more diverse microbiome. Your gut microbiota has a huge impact on your overall health. The diversity of plants included was a bigger factor than if they ate a vegan or omnivore diet. So it doesn’t mean only eating plants.
The Mediterranean diet is often heralded as the gold standard for a healthy diet. However, a consideration there is not just about the food. It’s tied in with how people live too. You could eat whatever the supposed “perfect” diet is on paper. But if you don’t look after yourself in other areas, it will have a detrimental effect on your overall health. This includes good sleep, regular exercise, being outside (or in nature, or in the sunshine), maintaining and having social connections, not smoking.
Nutrients intakes can be looked at on a sliding scale. Starting with deficiencies, when you are lacking (potentially seriously) nutrient(s). Then you have suboptimal, where your levels are low, but to a lesser extent. Next is an optimal range, and yes, this is usually a range rather than a strict fixed number. At the other end is too much, which depending on the type of nutrient can lead to toxicity.
The terms “high” and “low” in nutrition are far too frequently not defined. As an example, in studies looking at saturated fat intakes with Japanese cohorts, when you dig into the details, the high intake groups often have lower intakes than low groups in equivalent Western studies. The devil is always in the detail!
The dose makes the poison. You can have too much of anything. This is why black and white recommendations, “eat lots of x”, can be dangerous without proper definitions. Drinking too much water can kill you! (Hyponatremia). Equally, cutting something out, especially as drastic as whole food groups, can lead to deficiencies if you don’t then get key/essential nutrients elsewhere.
More detail on macros and micros here. However, to summarise, there is no perfect macro split.
This is quite an important point when changing your diet. If you remove anything, what is it being replaced with? Whether the change you make is a net neutral, positive or negative, will be dependant on that. Also, what aspect of your health are you trying to improve?
As another example, replacing saturated fat (SFA) with polyunsaturated fat (PUFA) has been shown to improve numerous health markers. However, replacing it with other nutrients (refined sugars, for one) can reduce some of the high risk health markers from a high SFA intake, but compared to the PUFA replacement was much less positive and raised risk levels elsewhere.
If you define your identity with your diet, what happens when you go “off-plan”? There are two sides to this coin. One if, it can be negative to tie it to your identity. For example I am vegan, instead of I eat a vegan diet. With the former, what happens if you are out and accidentally eat something that isn’t vegan? Or your mum made your favourite cake and it doesn’t happen to be vegan? You feel shame or guilt, as you are in conflict with your assumed identity. This ties in to the rules section below.
The flip side is when it comes to dieting, one study showed better adherence when it was tied to an identity. In that instance it may have been that changing the way the participants ate was bigger than their diet alone, and that was why they were more likely to stick with it?
Try to avoid restriction and strict rules. Dichotomous thinking (black and white/good and bad) and rigid dieting can lead to overeating or binging episodes, and is generally less successful for weight loss than flexible dieting. Having a more flexible approach, rather than rigid rules followed by blow-out ‘fuck-it’ days, will not only help keep a better relationship with food, it will also help with more consistent progress.
This also ties in with approach or avoidance orientated goals. Targeting what to include (an approach goal, such as I will eat a portion of fruit or vegetable with every meal) focuses on positive behaviours. Whereas having a large number of avoidance goals (such as, I will not eat sweets) is linked with having less satisfaction with the progress you make, along with decreased self-esteem and personal control.
Simply because something is labelled Natural, that doesn’t mean it’s healthy! It might be, but it also might not be! It we go back to plants again, there is plant-based diet index. A study looked at the difference between high quality plant foodss eaten (that includes minimally processed wholegrains, fruit, vegetables, nuts, seeds, legumes) compared with low quality plant foods (including highly processed foods, refined grains, refined cereals, fruit juice, pastries, jams and syrups). Consumers of the high quality plant foods were associated with a much lower risk of heart disease compared with those eating the low quality plant foods.
It can be complicated and there isn’t a simple guideline that will fit everyone. The main takeaway is to focus on the basics. There is no such thing as a perfect diet. If you get the foundations in place, the rest tends to look after itself. Some people like the 80-20 principle; healthy eating, whole foods, cooking at home for the large part, but 20% don’t worry. I personally quite like that, as it promotes flexibility and encourages people not to cancel social occasions in case they can’t account for the food there! (Red flag btw). In the UK we have the EatWell Guide too, which is actually not a bad place to start. It’s getting the pillars in place, then not stressing too much about the rest. Don’t forget, food should be enjoyed too.