Hi Reader,
Vitamin D. Vitamin B12. Iron. Magnesium. Zinc.
If one nutrient comes back low on a blood test, supplementation and dietary changes if applicable without much deeper investigation might be a good starting point.
But when I see someone with multiple deficiencies across the board, my thinking changes completely.
At that point, I stop asking, "What supplements do they need or what should they add to their diet?" and start asking, "Why is this body struggling to maintain adequate nutrient levels in the first place?"
Because by then, it's rarely just a deficiency issue.
It's often a digestion, absorption, utilisation, or increased physiological demand issue.
And that distinction changes everything.
Supplements are incredibly valuable. I use pharmaceutical-grade supplements extensively in my practice because they have an important role to play. They can replenish deficiencies, support underperforming systems, substitute where the body isn't producing enough, and accelerate healing when used strategically. But supplementation should never replace investigation. If we only correct the deficiency without understanding why it developed, we're often treating the consequence rather than the process that created it.
One of the biggest misconceptions is that nutrients simply move from food or supplements into the bloodstream.
They don't.
Every nutrient follows a remarkably complex journey. It first has to be released from food, broken down into a form that can be absorbed, transported across the intestinal lining, carried through the bloodstream, delivered into cells, and finally activated so the body can actually use it.
If any one of those steps is compromised, nutrient status begins to suffer.
This is why I often say that digestion is about far more than bloating or constipation.
It is the gateway to nutrition.
Take stomach acid, for example. Most people think of it only in relation to reflux or heartburn. But stomach acid is essential for liberating nutrients from food, particularly minerals like iron, zinc, calcium and magnesium, while also helping separate vitamin B12 from the proteins it's bound to. If stomach acid is inadequate, you can eat an excellent diet and still struggle to extract those nutrients efficiently.
Further down the digestive tract, pancreatic enzymes break proteins, fats and carbohydrates into absorbable molecules. Bile, produced by the liver and stored in the gallbladder, is critical for absorbing the fat-soluble vitamins A, D, E and K. Even the healthiest diet cannot overcome poor digestion if these systems are underperforming.
Then comes the small intestine — the primary site of nutrient absorption.
If the intestinal lining is inflamed or damaged, the surface area available for absorption is reduced. This means nutrients have fewer opportunities to cross into the bloodstream, regardless of how much is being consumed. Conditions that disrupt gut integrity, chronic inflammation, or persistent infections (including hidden infections) can all quietly impair absorption long before someone develops obvious digestive symptoms.
The microbiome also plays a far greater role than most people realise.
Beneficial gut bacteria help synthesise certain vitamins, influence mineral absorption, regulate inflammation, and maintain the health of the intestinal barrier. At the same time, certain pathogens and opportunistic microbes can interfere with nutrient status. H. pylori, for example, has been associated with impaired iron and vitamin B12 absorption, while some bacteria can compete with us for nutrients we consume.
And then there's another piece that's often overlooked entirely: utilisation.
Just because a nutrient enters the bloodstream doesn't mean the body can use it efficiently.
Many nutrients depend on other nutrients to become biologically active.
Vitamin D requires magnesium for its activation and function. Iron metabolism depends on adequate copper. Selenium is essential for converting thyroid hormone into its active form. Vitamin B12 and folate work together in methylation pathways. Deficiencies often occur in clusters because human physiology is deeply interconnected.
This is also why the form of a supplement matters.
Not all nutrients are equally absorbed or utilised.
Magnesium oxide, for example, is poorly absorbed compared with forms such as magnesium glycinate or magnesium malate. Some individuals respond better to hydroxycobalamin than methylcobalamin for vitamin B12. Heme iron is absorbed differently from non-heme iron. Curcumin requires specialised formulations to significantly improve its bioavailability.
Sometimes it isn't that the body needs more of a nutrient.
It needs the right form.
One of the biggest clues I look for in practice isn't an isolated deficiency.
It's a pattern.
Low vitamin D, iron, zinc and B12 appearing together tells me something very different from one isolated low result. It immediately raises questions about digestive capacity, stomach acid, gut integrity, microbial health, chronic inflammation, dietary intake, and whether the body's demand for nutrients has been significantly increased by long-standing physiological stress.
Those are the questions that move us beyond replacement and towards restoration.
This is why functional investigations are about far more than identifying what's low.
Comprehensive blood chemistry helps us identify nutrient patterns. Advanced functional testing, such as the GI-MAP, helps us investigate whether digestion, gut health, inflammation, or microbial imbalances could be contributing to those patterns. Together, they provide context that a nutrient level alone never can.
So, if you've recently discovered multiple deficiencies on your blood work, here's what I'd encourage you to consider before simply adding more supplements:
- Don't ignore supplementation—it has an important role. But don't stop there either.
- Ask whether the deficiency has an explanation, especially if it keeps recurring despite treatment.
- Make sure you're taking a well-absorbed, evidence-based form of the nutrient rather than assuming all supplements are created equal. Pharmaceutical-grade for the win!
- Think about digestion. Healthy stomach acid, pancreatic enzymes, bile flow, and an intact intestinal lining are just as important as the supplement itself.
- Look for patterns rather than isolated numbers. Multiple deficiencies often tell a much bigger story than a single low marker ever could.
Correcting a deficiency is important.
Understanding why it developed is where long-term healing begins.
If you’d like to explore whether this approach to healing might be the right fit for you, you can book a free discovery call below.
If there's anything specific you'd like me to discuss in my coming newsletters or have a question about something I've written, just reply to this email - I'd love to hear your thoughts/questions!
In good health,
Yukta,
Functional Diagnostic Nutrition Practitioner (FDN-P) &
Founder, Wellness Mastery Practice
