Are you sick of trying to work out what to eat? Nutrition science vs opinion is SUPER confusing – let’s clear things up.

Yes, nutrition is a field of science with years of evidence-based research behind it.

But like all sciences, there are a lot of opinions about what’s right and wrong in terms of healthy eating and nutrition.

Also, broad-brush general government eating guidelines and misleading media headlines add to the confusing storm of information.

No wonder people come to me and ask what they should eat to be healthy and/or lose weight….

“Can I eat fruit after 3pm?

“Should I follow a Paleo or HFLC eating plan?”

“Is gluten going to affect my gut?

“Can I eat bread, and if so, how much?”

If you’re wondering what to eat, I’ll explain it by walking you through a brief history of the things that have shaped my views on human metabolism, food and health – on nutrition science vs opinion.

The Biologist’s Perspective

Out of high school, I jumped into a Biology degree and at the same time, attained a ‘gym instructor’ certificate.

Sports nutrition was my amateur hobby.

Here’s what I learned about nutrition science vs opinion in these two areas of study.

Human Biology and Nutrition

In anatomy, physiology, biology, genetics and ecology, classes, I learned that:
  • humans are designed to be omnivorous (eat plants + animals)
  • a healthy body can maintain internal balance (homeostasis)
  • healthy balance and metabolism is challenged by stress, toxins, pollutants and stinking thinking (to borrow a great phrase from Paul Chek).

On that last point, a growing number of studies link stress, toxins and pollutants with poor digestion, nutrient absorption, gut issues, health complains and a frustrating inability to lose weight.

So even before you think about what to eat, consider your stress, exposure to toxins & pollutants and gut health.


All of these affect nutrient absorption, food intolerance, immunity and metabolism.

Population Biology and Nutrition

There are two main points here:

  • different groups of people are adapted to specific, locally available foods and climate.
  • certain populations have predispositions for certain food-related intolerances or allergies.

In the first case, genes are often part of that adaptation to specific foods.

For example, Inuit populations who eat the traditional diet of fish and fat and don’t get heart disease or weight issues. 

But if you take those Inuits off their standard diet and put them onto a Western diet, and they quickly get sick.

In the second case, some people just can’t tolerate certain foods and there are often genetic reasons. Here are some examples:

In other words:

Some people need to eat a high fat diet to be healthy, and others must have a low fat diet.

Some people can’t eat grains or drink milk without getting sick, while others can eat anything and everything without any impact.

When considering what to eat, consider your heritage.
Your body type and/or your genes might cause you to get sick from eating seemingly-healthy foods.

Plant Biology and Nutrition

Nutrition science vs opinion

From the plant biology point of view, there are three main points:

  • some plants are allelopathic, meaning they wage chemical warfare on the competing plants around them
  • the natural compounds in certain plant families may be toxic in high doses.

Here are two examples:

  • the oxalates/oxalic acid in spinach which can combine with (high intakes of) calcium to form kidney stones.
  • the alkaloids in the nightshade family (potatoes, capsicum, chilli, eggplant) which can cause gut, nerve and or joint issues in certain people who are sensitive to these alkaloids.

All this means that while some people can eat tomatoes and eggplants and feel ok, these foods will make others sick.

In addition, the healthiest and most disease-resistant plants usually grow in the most nutrient-rich soils.

Wrapping up on Biology:

Your genes (mutations, ancestry), body type and lifestyle habits (toxins, stress, gut health, mindset) predict the best types of food for good health and a healthy weight.  

Fitness Nutrition

Nutrition science vs opinion

The fitness industry is supposed to be the mecca of good health.

But working in this industry, I saw people preparing for bodybuilding competitions with super-strict diets that left them lethargic, dehydrated and cranky.

There were people following high carb diets and doing lots of aerobic activity and gaining more and more weight.

There were loads of women on crazy juice diets and shakes trying to get skinny.

There are lots of rules and fads that put many people on a treadmill of restriction, guilt and frustration.

And just like today, there were a LOT of different opinions about what to eat and when, how to be healthy, and which diet to follow.

Conflicting nutrition science vs opinion – and some very unhealthy mindsets – have always been rife in the fitness industry.

Having said that, there are a few people who get it right – a lean healthy body and a regular, mixed schedule of exercise without any manic dieting or crazy regimes.

One of the best and most confronting phrases I learned during my time in the fitness industry was this:

Nature doesn’t lie.

In other words, if you think you “eat pretty well,” then the truth is in the mirror.

If your body is overweight and sluggish, despite what you’re eating and how you’re training, then there is probably something wrong with what you’re eating.

Metabolic Typing and Nutrition

When I studied Metabolic Typing in 2009, so many things became clearer to me, and more specifically, it validated my thinking that customised nutrition was the way to go.

This field is what I call ‘biological nutrition’ because it wraps up elements of several nutrition protocols, including Ayurveda and the blood type diet…but it doesn’t dictate or preach a specific way of eating.

Rather, it provides a process to know and understand your own body and defines a framework to help you develop your own best way of eating.

I love this as it’s about you making the decisions, not someone else.

Within MT, the ‘Ayurveda’ component shows some interesting correlations between body type (frame size, muscle size and type) with specific foods. This ties in strongly with the PT-based nutrition course I studied.

And the assessment of the nervous and oxidative systems indicates which foods may potentially worsen cravings, anxiety, mood, sleep and weight imbalances.

Your body is as unique on the inside as it is on the outside.

It takes time and assessment to work out which foods are best for your unique body.

Nutrition Science vs Opinion

Let’s get to pure nutrition science.

The Accredited Cert of Nutrition I studied in 2013 is an example of a pure nutrition science course.

It taught current facts about carbs – glycemic index, glycemic load, and weight-management issues around specific foods.

This course compared the values of whole foods with those of processed foods, and considered calorie intake and nutritional value of foods.

While I learned the well-studied facts on nutrition, it was reminded that:

  • facts are often not enough to sway opinion. People like to hold on to what THEY think is right,
  • facts are not enough to motivate change. We all know what to do, but we don’t do it, and
  • nutritional needs vary with age, stage of life, level of activity and health status.

There is a real need for education to explain the facts about healthy food.

However, education is just ONE part of the solution.

You ALSO need to know how to apply it in a way that is relevant to your genes, body and lifestyle.

Health and Wellness Coaching and Nutrition

Nutrition science vs opinion

My scientific mind causes me to question and dispute what I hear in order to find the truth.

As a scientist, I know how often and easily data are manipulated to present a certain point of view.
My curiosity and creativity and love of learning mean that I am always experimenting and questioning things, trying new recipes, testing eating protocols, working out what’s real and what’s fake.
But even when you know what to do, or which recipe to follow, or how to substitute wheat flour with coconut flour…it doesn’t mean you’ll develop consistent and/or healthy habits.
That’s probably why studying Coaching Psychology via Health and Wellness Coaching Certification had the biggest impact on me.
I learned the most important lesson – that telling, suggesting, advising, recommending, coercing, cajoling, convincing, diagnosing, prescribing or analysing people doesn’t work.
We all want to be our own masters and write our own rules.
You may need help to look at your life and discover what those rules are – then to build the confidence and motivation to help you act on your discoveries.

This was the final piece of the puzzle for me.

Telling people what to do and prescribing diets doesn’t work.

What DOES work is discovering your own truth, and write your own rules.

It can be difficult and time-consuming to do this on your own, without someone to talk to, put you in charge, keep you focused, support you and hold you accountable.

Yet at the same time, your logical brain sabotages you by saying “I should be able to do this myself.”

As someone who works in this field, this was my hardest lesson and it took me a long time to ask for help.

And when I finally did, I kicked myself for not having done it sooner, because I learned so much about myself simply by having someone listen, reflect and ask the right thought-provoking questions that helped me discover my own answers.

Having a plan and some accountability made sure I took the required actions to get back on track.


Nutrition Science vs Opinion Summary

In summary, “nutrition” is full of facts but is heavily swayed by opinion.

It is up to YOU to find your own best way of eating for health, energy, vitality and a healthy weight.

There are many clues in your history and makeup to help you find a starting place to define your own food rules.

The first and best thing you can do for yourself is stop reading all the news and media about “superfood this” or “new diet that”.

What you DON’T need is to be dependent on someone to tell you what to eat and when.

What you need is the help to discover what works for you, and to help you build the confidence, motivation and plan to actually DO it.

If you need help to work out what to do, untangle the confusing mess that is nutrition science vs opinion, and write your own healthy eating and lifestyle plan, reach out get in touch.

Book a chat with myself or one of our coaches. It’s free. And it might change your life.

Melanie White

Melanie White

Chief Inspiration Coach

I’m a quirky scientist and a Health and Wellness Coach who helps 35+ women to understand and eat right for their body type.