Personalized diet: What is it and do you need one for you?

No two people think alike and our body types are no exception to it. All humans are made different and so is their physical requirement. According to some scientists, “one size doesn’t fit all when it comes to healthy eating advice” and thus arises the need of having a personalized diet.  However, there’s no particular definition of personalized nutrition or diet. So, let’s define it as an approach that takes into account individual characteristics and based on such information develops targeted nutritional advice, products, or services to assist individuals in achieving a lasting dietary behaviour change.

This information consists of factors like your genetics, gut bacteria, eating habits, body measurements, weight, cholesterol levels and lifestyle, or an overall combination of all these factors.

Knowing the same, some dieticians have been offering personalized diet advice for decades, but developments in the understanding of factors that affect our individual digestive and metabolic profile still have a long way to go. However, improving technology has enabled us to test some of these things to try new methods of incorporating these personalized diets into our daily life.

Personalized diet is commonly known by people by a variety of alternative names such as "precision nutrition," "individualized nutrition," and "nutritional genomics”, and these terms keep on adding volume and meanings to the term.

Why do you need to have a personalized diet?

We are not alien to the handicap of chronic diseases. And what is the reason for the same? Well, at the root of almost all health-related crises is “poor nutrition”.

Conditions like cardio-metabolic conditions and diet-related cancers are among the major leading factors of death worldwide. Meanwhile, a countless number of evidence suggests that consuming a healthy diet that is abundant in fruits, vegetables, whole grains, legumes, and nuts is associated with lower levels of these diseases and significantly reduces the risks of such diseases across various adult subgroups.

A few of the factors that have much relevance to a personalized diet are – nutritional genomics, metabolomics, proteomics, micro-biomes epigenomics, and transcriptomics. Even if these terms may sound inconsequential to us, these analyses identify the most important molecules such as metabolites, proteins, microbes, and genes in our body. These factors are crucial as they conduct investigations on our body system function and take into account its nutritional and environmental facets allowing the experts to understand an individual's specific needs in a much finer way.

From which, the microbiomes play a vital role in the efficient functioning of the gut. Though it’s quite difficult to define what a 'healthy' microbiome exactly is, as there exist certain variations according to a person's age, environment, or diet, a healthy gut microbiome can nevertheless be characterised by its diversity, stability, and capacity to fulfil metabolic functioning. These microbiomes play an important role in performing the activities such as –vitamin production, developing immune system development, epithelial homeostasis, and metabolite production.

Opting for a personalized diet plan is equally helpful for those who are nutritionally healthy and may or may not have enhanced genetic susceptibilities to specific diseases as well as for those who are already facing such circumstances i.e. the patients.

A personalized diet can be broadly applied in two major areas –

Firstly, for those who need dietary management with specific diseases or who need special nutritional support such as pregnant women or old people, and secondly it is important for the development of more effective interventions needed to improve public health.

Traditionally the concept of personalized nutrition has been associated with maximising the benefits and reducing the adverse effects of dietary changes for the individual, however, due to its primary focus on the individual it may have a limited impact on populations.

In other ways, to create a wider impact i.e. on people worldwide, it must be deployed at a scale and in a way that reduces (rather than increases) health disparities. Individuals may also adopt the habit of personalized nutrition to achieve personal goals/ambitions that are less directly related to health such as dealing with preferences for, and dislikes of specific foods, achieving a desired physical shape or change, etc.

How is a personalized diet conceptualized?

Personalized nutrition is an abstract idea that emerges from the need or requirement of an individual’s nutritional advice, products, or services which will prove to be more effective than more generic approaches

It is based on –

1.      The biological structure of an individual or evidence of differential responses to foods/nutrients dependent on their particular genotypic or phenotypic characteristics

2.      Analysis of current behavior, preferences, barriers, and objectives and subsequent delivery of interventions, as these factors motivate and enable each person to make appropriate changes to his or her eating and dietary pattern.

Challenges to implementing personalized nutrition in your life –

There exist quite a number of problems and challenges that one needs to overcome before fully realizing the benefits of personalized nutrition. These challenges are concerned with data and methodological issues, level of education, and a consideration of the ethical and legal aspects involved in the same.

Firstly, as bioinformatics has expanded and vast data is available in our hands, it presents us with a challenge that nutritional experts are only too keen to surmount. Collecting, organizing, and analyzing these datasets is a huge task, and it also proves to be quite time-consuming and expensive. Also, due to the complexity of the data, drawing conclusions from it can also prove controversial. And the result from clinical trials regarding the same seems to be questionable at times because of a lack of reproducibility.

Another major challenge that proves to be challenging in the matter is that of education. Nutritional practitioners, including primary care physicians and registered dietitians, are required to increase their knowledge about the latest developments in the field of personalized nutrition as it is also an undertaking for the entire health care team.

And lastly, the ethical and legal aspects need to consider things furthermore thoroughly, such as, they need to ensure the protection of consumer privacy associated with the use of technologies and tests of such studies.

And this call for us to understand the effectiveness of a personalized diet i.e. the strengths and weaknesses of that personalized diet –

What are the strengths and weaknesses of a personalized diet or nutrition?

Strengths –

•        On certain occasions personalization results in greater and even more powerful improvements in the diet than universal approaches.

•        Due to personalization, at times one may foster sustained change in their behavior.

•        The need for a personalized nutrition approach mirrors and teaches people about the rise in personalized, or precision. And these personalized developments lead to personalized nutrition, and, therefore help and affect public health.

Weaknesses –

•        Personalized nutrition is mostly based on observational studies and aligned with scientific evidence and a low level of reproducibility.

•        The theoretical basis for personalized nutrition is yet to be developed.

•        The dietary factors which are responsible for the inter individual differences as a response to the changes and their persistence over time within the same individual and the scope of its inheritability are mostly unknown to all.

•        A handful of such well-designed circumstances exist that demonstrate the efficacy and safety of following a personalized diet.

•        Most of the commercial offerings in the personalized nutrition area are related directly to consumer tests that are unregulated and have limited published evidence of significant benefit.

Key things to remember and consider while opting for a personal diet –

•        Personalized nutrition takes into account an individual’s characteristics to develop targeted nutritional advice, products, or services. These characteristics are needed to achieve a lasting dietary change in behavior that is beneficial for leading a quality life and maintaining good health.

•        A personalized diet is based on the concept that individualized nutritional advice, products, or services, i.e. focusing on particular individual needs prove to be more effective than the traditional generic approaches.

•        Personalization can be based on either biological evidence comprising of differential responses to foods/nutrients depending on genotypic or phenotypic characteristics, or it’s either based on the individual’s current behavior, preferences, barriers and objectives.

•        Most of the evidence that is available that has come from the observational studies made in support of personalized nutrition has however included a few risk factors as outcomes. However, consulting with your doctor after knowing what is good and bad for your body you can definitely go for your own personalized diet.