In my last article, we talked about why “normal” doesn’t always mean “optimal” and how bloodwork can provide valuable insight into what’s happening inside the body. One of the most common questions I hear afterward is, “So, what numbers should I actually pay attention to?”
The answer is that every person’s health story is different. There isn’t one lab marker that tells us everything. Instead, we look at the bigger picture and how different markers relate to each other and, most importantly, how they relate to how you’re feeling.
Here are some of the bloodwork markers I find myself discussing most often with clients.
Ferritin: More Than Just Iron
Many people are surprised to learn that ferritin and iron are not the same thing.
Ferritin is your body’s storage form of iron. Think of it as your savings account. Even if your iron level appears normal on the day your blood is drawn, low ferritin may suggest your body doesn’t have enough stored away for future needs.
When ferritin is low, people may experience fatigue, hair thinning, poor exercise recovery, shortness of breath, restless legs, headaches, or difficulty concentrating. These symptoms are often dismissed because iron levels themselves may still fall within the laboratory’s reference range.
Understanding ferritin helps us ask a much bigger question: Why are iron stores low in the first place? Nutrition, digestion, heavy menstrual cycles, medications, inflammation, and gut health can all play a role.
Fasting Insulin: An Early Clue
Blood sugar often receives most of the attention, but fasting insulin can provide information much earlier.
Insulin is the hormone that helps move sugar from the bloodstream into our cells. Long before blood sugar begins to rise, the body may start producing more insulin to keep glucose in a normal range.
This can sometimes explain why someone struggles with weight resistance, increased cravings, afternoon energy crashes, or feeling hungry shortly after eating, even when their glucose and A1C still appear normal.
Looking at insulin gives us another piece of the metabolic picture rather than waiting until problems become more advanced.
Vitamin D and Vitamin B12
Vitamin D is well known for supporting bone health, but its role extends much further. It also supports immune function, muscle health, mood, and many other important processes throughout the body.
Vitamin B12 is essential for healthy nerve function, red blood cell production, and energy metabolism. When levels are less than ideal, people may experience fatigue, brain fog, tingling sensations, memory concerns, or difficulty concentrating.
These vitamins are excellent examples of why understanding the whole clinical picture matters. A laboratory value is important, but so are a person’s symptoms, lifestyle, nutrition, medications, and health history.
Thyroid and Inflammation
Many people believe that a thyroid evaluation begins and ends with TSH. While TSH is an important screening tool, it represents only one piece of thyroid function.
Depending on the individual and their symptoms, additional thyroid markers may provide a more complete understanding of how the thyroid is functioning.
I also frequently review inflammatory markers such as hs-CRP. Inflammation is a normal part of the body’s healing response, but when it remains elevated over time, it may contribute to a wide variety of chronic health concerns. Like every other marker, it should always be interpreted within the context of the entire person—not in isolation.
Bloodwork isn’t about chasing perfect numbers or becoming overly focused on individual results. It’s about gathering information, recognizing patterns, and using that knowledge to make informed decisions that support long-term health.
Every lab marker tells part of the story. When we take the time to understand how those pieces fit together, we gain a clearer picture of how our bodies are functioning—and where there may be opportunities to support better health.
In my next article, we’ll discuss how to prepare for bloodwork, why timing matters, and a few simple steps that can help ensure your results provide the most accurate and meaningful information possible.
Your Partner in Health,
Reg
