“I tried a supplement that my friend praised highly, but I felt no change at all.”
“Even with similar diets, some people gain weight while others lose weight.”

Many of you may have had similar experiences or questions.

Why does a health approach that feels like a “miracle cure” for one person not work for another—or even work against them?
This is not a matter of willpower or effort.

It is because there are decisive individual differences in our “genes,” which are the blueprint of the body, and in our “metabolic capacity,” which determines how substances are processed.

In this article, we will examine the medical reasons why there is no single answer that applies to everyone.

“Alcohol tolerance” is one of the most familiar individual differences

“Individual differences” may sound abstract, but one of the clearest examples is alcohol.
Some people turn bright red after one glass, while others can drink all night without issue.

This is largely determined by genetic differences in the activity of enzymes that break down alcohol (such as ALDH2). No amount of training or mindset can change the enzyme type you were born with.

In fact, the same kind of difference occurs with NMN and other supplements, pharmaceuticals, and essentially all everyday nutrients.

When you take a nutrient, some people have a “fuel-efficient constitution” that can convert it into energy efficiently, while others have a “fuel-inefficient constitution” in which it is not absorbed well and passes through without being utilized.
This is the difference between “responders” (those who respond) and “non-responders” (those who do not respond) in medicine.

The operating rate of the body’s “factory” differs from person to person

Inside our bodies, chemical reactions are continuously occurring to generate energy and repair cells using the substances we ingest. This is called “metabolism.”

Imagine your body as a huge chemical factory.
In that factory, many “workers (enzymes)” process substances.

• A factory with diligent and abundant workers (high metabolic activity)
  When materials (supplements, etc.) come in, they are more likely to be quickly converted into products (energy and repair-related substances). = “Tends to be easier to feel effects”
• A factory with few workers, or workers who are not functioning well (low metabolic activity)
  Even if materials come in, the line may stall, and the materials may be discarded (excreted) without being processed. = “Effects may be difficult to obtain in some cases”

What requires further caution is the possibility that unprocessed materials can accumulate in the factory and build up as “waste (metabolic byproducts).” Research has pointed out that even high doses of vitamins and minerals taken with good intentions may, depending on a person’s metabolic capacity, place a burden on the body.

Let go of the illusion of “average”

Over-the-counter supplements and general health guidance are designed based on an “average person.”
However, as discussed, when viewed at the genetic level, an “average person” does not truly exist.

Imitating someone else’s success story without knowing your own “blueprint (genes)” and “factory operating status (metabolism)” is like wearing someone else’s shoes without knowing your foot size. If the size doesn’t fit, even the finest shoes will cause blisters.

That is why medical institutions focus on “tailor-made (personalized medicine)”.

Confirming your blueprint through genetic testing and understanding your actual metabolism through blood and urine tests.
Only then can you begin to see “the optimal amount for you” and “ingredients that may not suit you.”

Key takeaways from this article

• The reason there is no “health method that works for everyone” is that, just like alcohol breakdown capacity, nutrient metabolism also differs among individuals (differences in genes and enzyme activity).
• Even when taking the same ingredient, some people may not experience effects (non-responders), and there may also be a risk of burden if the body cannot metabolize it sufficiently.
• Rather than imitating others, understanding your own “metabolic characteristics” is a practical path toward more efficient health investment.

Recap

In this article, we explained that there are meaningful individual differences in our bodies and that a one-size-fits-all approach has limitations. We hope this helped you understand the importance of knowing your own “metabolic capacity.”

Now, even if you understand your constitution, the next key point is the strategy of “how to deliver ingredients.” No matter how good an ingredient is, it has limited value if it does not reach where it is needed (such as the brain or cells).

Next time, we will explain the science of “administration routes (DDS: Drug Delivery System)” used in clinical practice—not only supplements (oral intake) but also injections, IV infusions, and nasal administration.