Ever met a mechanic at a social event and the first thing that comes out of your mouth is a question about some ‘strange happening’ to do with your car? One of my sons is an apprentice mechanic. He gets this often. Funnily enough, I get this too, but not to do with cars. Whenever I mention to someone that I am a Nutritionist, they start asking questions about their health. One of the most common questions is “What the heck am I meant to eat?” This is usually followed by some sort of question about whether they should be limiting carbs, or cutting out meat, or only eating meat (that is a thing, you know – it’s called the Carnivore Diet). There is so much confusion around healthful diets, and what we should be eating. Open any magazine, or glance over your Facebook feed and you will see some celebrity touting the benefits of a particular eating regime.
How did things get so confusing?
For most of us, our nutritional education started in our early years at home. We probably learned to label foods as either good or bad, with this differentiation being based on whether we liked the food or not, rather than on its nutrient profile. We also had our parents telling us to “eat our greens” – which was very good advice, and to “finish the plate because there are starving children” – I never quite understood how finishing my meal here, affected anyone else, anywhere else, but thanks Mum for making me a more aware citizen.
Then in school we may have learned of the Australian Food Pyramid. Remember this?
Australian Food Pyramid by Nutrition Australia, 1999
Further education may have come from the packaging on the foods we regularly ate. This may have been from advertising slogans, like ‘Iron Man Food”, their star ratings or the number of health ticks. We may also have learned about nutrition from friends and colleagues who have tried out various eating paradigms, such as Paleo, or Veganism.
Despite the knowledge we have acquired along the way, there is still confusion about what we should be eating. Do you find yourself in this same boat? Confused and in a state of analysis paralysis?
Let me tell you how I answer the question, though it’s probably not the answer you are hoping for. You probably want me to tell you there is one right way to eat, and that all the other dietary paradigms are wrong. Sadly, my answer to that question is that it depends?
Let me explain…
It depends on your genetic heritage
It depends on your stage of life
It depends on whether you are experiencing ill health
It depends on the signs and symptoms you are experiencing
It depends on whether you have food intolerances
It depends on how the food you eat was grown and stored
It depends on your cooking abilities
It depends on your budgets and circumstances
And It also depends on what you enjoy eating…
Let’s start with heritage. In the past, food consumption was closely tied with the locations we lived in. Over many, many generations, our bodies adapted to these circumstances, and humans were able to live reasonably well in a variety of locations. An example of this involves consumption of dairy products, which were a common source of nutrition in Northern Europe. As such those living in this location developed the ability to tolerate lactose well beyond the infant years. Another example involves those of Asian descent being better adapted to consume soy based foods than those from Europe, where soy wasn’t a source of nutrition prior to the last 150 years.
The challenge for us now is that we are eating foods that are grown and manufactured from locations over the world. This is wonderful for diversity in our food supply, but it may also mean we are not well adapted to eating some of these foods, especially in the quantities we are consuming them. Additionally, many of our foodstuffs have filler ingredients that our bodies may not recognise and process suitably.
Our stage of life will also affect our dietary requirements. Think of those lanky teenage boys who seem to be perpetually hungry. They are growing rapidly, and growth requires a consistent supply of nutrients. Compare that with those in their later years who are fairly sedentary. They tend to eat like birds, and still cope well for the most part. When we consider the types of foods we consume, we need to factor in periods of growth and provide the necessary building blocks through the diet to sustain good health. The teenage years are often a time when young people are experimenting with various dietary paradigms, for example vegetarianism. Unfortunately, the teenage years are also a time where a higher protein diet is required to sustain growth. This mismatch between need and supply may lead to poor health, if not managed wisely. Pregnancy would be another time when there are high nutrient requirements. We need to provide our bodies with the building blocks it needs for periods of growth.
The types of signs and symptoms of illness may indicate the need for the short-term adoption of specific healing type diets. For example, an elimination diet can be helpful in bringing to our awareness the possibility of food intolerances. In this approach, people remove various foods such as gluten, dairy or eggs from the diet for a number of weeks, followed by a slow, methodical reintroduction of these foods. This exercise is used to ascertain whether symptoms of ill health correlate with the ingestion of various foods. A more extensive version of the elimination is the Autoimmune Paleo or AIP diet that aims to help those experiencing the symptoms of various autoimmune conditions. This diet eliminates many more of the potentially allergic foods, and uses a paleo template to help those with autoimmune conditions manage and improve their symptoms. It involves removing grains, dairy, nuts, seeds, legumes, nightshades, sugar, eggs, industrial oils, food additives and alcohol. Similar to the basic elimination diet, after these foods have been removed for a period of time, they are slowly reintroduced, again watching for symptom correlation.
Another type of healing diet is The Low FODMAP diet. This diet is commonly recommended for those experiencing Irritable Bowel Syndrome (IBS). Foods that are high in FODMAPS (fermentable oligosaccharides, disaccharides, monosaccharides and polyols), which are components of foods found in wheat, rye, onions, garlic, legumes, pulses, lactose, fructose, sugar alcohols such as sorbitol and mannitol and honey. After symptoms improve these foods are slowly and methodically reintroduced to look for symptom correlation. Ideally this is not a long-term diet, as other factors at play in IBS can be addressed during the elimination and hopefully many foods can be reintroduced in the longer term.
There are plenty of other diets and food paradigms that have shown positive health benefits in research. A low glycaemic diet might be recommended for those experiencing blood sugar dysregulation. The Mediterranean diet has lots of evidence to back its success in reducing risk factors associated with cardiovascular health and cognitive decline. The ‘keto’ diet (high-fat, low-carb) has evidence to back its benefits in those experiencing seizures. It is currently very popular for weight loss, and general health. No wonder there is so much confusion about which diet is the best for health.
What the scientists say…
In 2014 Katz and Meller, two eminent nutritional scientists were commissioned to carry out research in an attempt to answer the question of which diet is the best for health. Their research was published in the Annual Review of Public Health that same year. Unfortunately their research found it was not possible to determine an outright winner for the healthiest diet. Certainly, if the scientists can’t do it, it makes us feel better when we can’t work it out either.
The most interesting aspect of their research had to do with the commonalities of the various dietary approaches, rather than their differences. Their research focused on 7 of the most popular dietary paradigms, and despite their striking and often contradictory differences in ideology, they found there were 4 factors they all had in common. Their summation is that it may be these factors that provide the health benefits in preventing and managing many of the ailments prevalent in society today.
These commonalities include:
- Limiting refined starches and added sugars from the diet
- Limiting processed foods
- Limiting the intake of certain types of fats, and incorporating healthy fats such as olive oil
- Providing an emphasis on whole plant foods (with or without lean meats, fish, poultry and seafood)
The New York Times bestselling author, Michael Pollan, summed these commonalities up in his book titled “In Defence of Food”. He said, “Eat food, not too much, mostly plants”. His book offers some great insights. It’s a sensible approach to healthful eating, without recommending any specific dietary paradigm, he guides his readers to individually adapting whatever dietary paradigm resonates within a health giving framework. His first recommendation is that we should eat food – real food. His sage advice is to not eat anything your great-great grandmother wouldn’t recognise as food. He added that we also shouldn’t eat anything that is incapable of rotting. Many products on our supermarket shelves today contain preservatives and adulterated fats that allow for extraordinarily long shelf lives. This is great for retailers, but not so great for our bodies that don’t handle these foods well.
And why should we eat mostly plants? Plant foods, especially green leafy vegetables are full of phytonutrients which is essential for good health. They have abundant fibre which is an important food source for our gut microbiota. They are also energy and nutrient dense, leading to us eating less, which leads to another of his recommendations. Why is it helpful to not eat too much? The Japanese have a saying hara hachi bun me (or hara hachi bu) which is an old Confucian teaching suggesting people only eat till they’re 80% full. This practice is commonplace in Okinawa, which is renowned for having the highest percentage of centenarians in the world. They have another saying that the first 80% of what you eat sustains the person, the other 20% sustains the doctor. Enough said?
To summarise, the best diet for health will depend on many factors. We are all individuals, and these factors will vary, depending on our current state of heath, our age, and our heritage. There is likely no one particular diet that is healthful for everyone, in every circumstance, but there are some guiding principles that we can incorporate within which ever diet we choose to follow. These include eating whole foods in their least processed state, incorporating as many plant foods as possible, choosing healthy oils, and reducing or better yet, eliminating refined carbohydrates such as sugar.