Metabolic Health as a Root Driver for Cognitive Health
Protocol development in integrative medicine is not typically a simple process. Individuals require individualized care, and what works for one patient may not work for another.
To establish these protocols, we first developed a Rating Scale that could be used to discern the rigor of evidence supporting a specific nutrient’s therapeutic effect.
The following protocols were developed using only A through D-quality evidence.
Introduction
What Is Cognitive Support for Health Aging?
Cognitive health encompasses the capacity to maintain attention, memory, and mental clarity by supporting the systems that influence brain function. These include mitochondrial efficiency, antioxidant capacity, inflammation balance, adequate nutrient status, and circadian rhythm alignment. (Jost 2025)(Melzer 2021)(Wright 2015)
This clinical guide emphasizes proactive, measurable approaches that specifically target metabolic health to help sustain optimal brain performance and overall vitality across the aging process.
Why Metabolic Health Matters
Metabolic health is increasingly recognized as a critical determinant of cognitive function, given the brain’s high metabolic demands and dependence on tightly regulated glucose and insulin signaling. Insulin resistance, type 2 diabetes, obesity, and metabolic syndrome (MetS) are associated with neuroinflammation, oxidative stress, endothelial dysfunction, and impaired cerebral glucose metabolism, all of which contribute to cognitive decline. Insulin plays a direct role in synaptic plasticity, neurotransmitter regulation, and memory consolidation, and disruption of central insulin signaling has been implicated in the pathophysiology of Alzheimer’s disease (AD), sometimes described as “type 3 diabetes.” (Craft 2009)(Arnold 2018)(Ponce-Lopez 2025)(Yaffe 2004)(Steen 2025)
MetS—or having 1–2 components of MetS (i.e., blood sugar dysregulation, hypertension, dyslipidemia, or abdominal obesity)—increases the odds of poor memory performance. A 2023 meta-analysis of 122 studies found that diabetes mellitus increases relative risk for cognitive impairment and dementia by 1.25 to 1.91 times. Additionally, metabolic dysfunction increases the risk of cerebrovascular disease, increasing the risk of vascular cognitive impairment and mixed dementia. (Alsuwaidi 2023)(Sebastian 2023)(Arnold 2018)(Yaffe 2004)
Purpose of the Clinical Guide
The Metabolic Health as a Root Driver for Cognitive Health clinical guide was designed to:
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- Simplify decision-making using standardized, evidence-rated nutrient interventions.
- Integrate laboratory and biomarker data to identify modifiable metabolic contributors to cognitive health.
- Complement the Cognitive Essentials for Healthy Aging clinical guide, enabling providers to integrate metabolic-focused strategies alongside foundational interventions when addressing cognitive health and function.
Labs
Fasting Blood Glucose
Fasting glucose levels provide valuable insights into the body’s ability to regulate blood sugar. They’re a crucial indicator of metabolic health and an essential tool for the early detection of metabolic disorders. A fasting blood glucose test result between 70–99 mg/dL is considered normal, levels between 100–125 mg/dL relate to prediabetes, and levels of 126 mg/dL or higher on two separate tests usually relate to diabetes. (Mathew 2023)(Nakrani 2023)
Insulin Resistance Panel
Insulin resistance panels can provide a comprehensive evaluation of insulin resistance by combining measurements of fasting insulin and C-peptide using advanced LC/MS/MS technology. Insulin resistance panels can offer a more accurate assessment of metabolic health than traditional glucose tests alone, as they can detect early signs of insulin resistance before glucose levels become elevated. (Cho 2022)(Nolan 2019)
Hemoglobin A1c (HbA1c)
HbA1c provides insights into the average blood glucose levels over the previous 2–3 months, making it a crucial biomarker for assessing long-term glycemic control and metabolic health. Beyond its role in diagnosing and monitoring diabetes, HbA1c has been shown to correlate with insulin resistance, cardiovascular risk, and other components of MetS, making it an important tool for evaluating overall metabolic health even in nondiabetic individuals. (Osei 2003)(Sherwani 2016)
Oral Glucose Tolerance Test (OGTT)
The OGTT provides insights into diabetes mellitus status, insulin resistance, and impaired pancreatic β-cell function. A dose of glucose is administered orally, and blood glucose levels are measured after two hours. (Zubair 2025)
Lipid Panel
A lipid panel evaluates a patient’s lipid metabolism and cardiovascular risk. It typically includes measurements of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides, with some panels also reporting non-HDL cholesterol or calculated ratios. Results are interpreted in the context of the patient’s overall clinical profile, including age, sex, comorbidities (such as diabetes or MetS), family history, and use of lipid-altering medications. (White-Al Habeeb 2023)
Advanced Lipid Markers
Advanced lipid markers may provide a clearer picture of a patient’s cardiovascular (CVD) risk. Apolipoprotein B is a strong indicator of coronary artery disease (CAD), and it can be elevated even when LDL cholesterol levels are normal, helping to identify risk in patients who might otherwise be considered low-risk based on cholesterol alone. Increased concentrations of Apolipoprotein A1 are associated with reduced risk of cardiovascular disease. Elevated concentrations of lipoprotein (a)—Lp(a)—are associated with increased risk of coronary artery disease. (Quest Diagnostics n.d.)
Comprehensive Metabolic Panel (CMP) – Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT)
Higher AST levels and lower ALT levels have been associated with an increased risk of cognitive decline and dementia. Elevated AST and AST to ALT ratio have been correlated with poorer cognitive performance, while reduced ALT has been linked to lower cognitive scores and greater dementia risk. Liver enzyme imbalances have also been associated with structural brain changes in regions such as the hippocampus, amygdala, and thalamus, suggesting that liver dysfunction may contribute to neurodegeneration and cognitive impairment. (Gao 2024)
Gamma-Glutamyl Transferase (GGT)
Elevated serum GGT levels are associated with increased risk of dementia, including AD and vascular dementia, likely reflecting pro-oxidant pathways contributing to neurodegeneration. (Han 2020)
Ingredients
Protein Powder
Dosing: Start with a general dose of 10–20 g daily of plant-based or whey protein (although dosages are typically in the 20–40 g range)
Supporting evidence:
- Healthy adults engaging in minimal physical activity should aim for at least 0.8 g of protein per kg of body weight per day to meet the recommended dietary allowance (RDA) of protein to avoid deficiency. This translates to about 10–15% of total daily energy expenditure.
- Daily protein intake should be adjusted depending on age, physical activity, and metabolic health goals. Studies suggest that a high-protein diet consisting of 1.07–1.6 g of protein per kg of body weight daily (27–35% of total daily energy expenditure) provides enhanced weight-loss effects while preserving fat-free mass. (Bray 2024)(Moon 2020)
- GLP-1 secretion is enhanced by all forms of dietary proteins (from whole proteins to peptides and amino acids), each interacting with unique or unknown cellular mechanisms based on their structure. (Hira 2021)(Miguéns-Gómez 2021)(Volpi 2001)
Glutamine
Dosing: 15–30 g daily (Meek 2016)
Supporting evidence:
- A review article summarizing findings from multiple animal, cell model, and human studies investigated the effects of various food factors, such as amino acids, including glutamine, on GLP-1 secretion and their potential impact on glucose metabolism. Glutamine, in particular, was shown to elevate cytosolic calcium and cell adenosine 3′,5′-cyclic monophosphate (cAMP) in enteroendocrine L cells, promoting GLP-1 secretion in experiments. This suggests that glutamine could play a role in improving glucose tolerance by stimulating GLP-1 secretion. However, the study also notes that effective doses of glutamine (15–30 g) are needed to achieve beneficial metabolic effects in humans, as lower doses have not consistently led to significant metabolic improvements. (Meek 2016)
Soluble Fiber
Dosing: 5–10 g daily
Supporting evidence:
- Soluble fibers, including guar gum and larch arabinogalactan, can support metabolic health by moderating energy intake, stabilizing postprandial blood glucose levels, and improving satiety, ultimately addressing risk factors for obesity, hyperglycemia, and hypercholesterolemia. These ingredients are resistant to digestion and promote beneficial gastrointestinal microflora and short-chain fatty acid (SCFA) production, supporting a healthy gut environment that favors comprehensive metabolic health. (den Besten 2015)(Dion 2016)(Kim 2002)(Wu 2023)
Vitamin D3+K2
Dosing: 5,000 IUs (adjust dose based on testing) plus 25–95 mcg daily (depending on the dose of vitamin D)
Supporting evidence:
- Vitamin D+K supplementation is linked to improved metabolic health, GLP-1 levels, and bone health. (Kuang 2020)(Pazarci 2019)(Zhang 2021)
Beta‐Hydroxy‐Beta‐Methylbutyrate (HMB)
Dosing: 2,000 mg daily
Supporting evidence:
- HMB is a metabolite of the essential amino acid leucine. It has been shown to effectively mitigate age-related declines in lean mass, while also enhancing muscle strength and functionality in older adults. These benefits may be enhanced with vitamin D3 supplementation. (Flakoll 2003)(Rathmacher 2020)(Wilson 2008)
Disclaimer
The Fullscript Integrative Medical Advisory team has developed or collected these protocols from practitioners and supplier partners to help health care practitioners make decisions when building treatment plans. By adding this protocol to your Fullscript template library, you understand and accept that the recommendations in the protocol are for initial guidance and may not be appropriate for every patient.
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