How Human Migration Shaped Our Metabolism
We all have different genetics, different body types, and different tendencies when it comes to metabolism—and insulin resistance is no exception. While insulin resistance is largely lifestyle-driven, there’s a very real genetic piece that plays into your personal risk.
So let’s rewind tens of thousands of years.
As humans migrated out of Africa and into every corner of the world, we adapted to the climates, environments, and food availability around us. This shaped everything from skin tone to digestion to—yes—how much insulin we produce. And these adaptations still influence us today.
Let’s break it down by major ancestral populations to see how this plays out in real life.
African and Black Populations
Populations with Sub-Saharan African ancestry often have a high insulin response to food. They tend to oversecrete insulin and also have a reduced ability to clear insulin from the blood. Historically, this was an incredible survival advantage—higher insulin levels meant more fat storage, which offered protection during times of famine or food scarcity. But in today’s world, where food is constantly available and often ultra-processed, this same trait can become a serious liability.
It leads to a greater risk of weight gain, chronic inflammation, and metabolic diseases.
This helps explain why African American and other Black populations experience some of the highest rates of insulin resistance, Type 2 Diabetes, and PCOS—even at lower body weights. And it’s also why obesity is so prevalent in these communities. It’s not a lack of willpower—it’s how the body is wired. The issue isn’t eating too much. It’s eating in a way that constantly spikes insulin in people who are genetically predisposed to overproduce it.
To make matters worse, many diseases are more aggressive in these populations, including Alzheimer’s, multiple sclerosis, and cardiovascular disease. It all traces back to the underlying chronic inflammation fueled by insulin levels that stay high for too long.
This is why the solution isn’t “calories in vs calories out”—it’s eating in a way that works with your biology to keep insulin levels stable. When you lower insulin, you calm inflammation, and improve metabolic health.
East Asian Populations
On the flip side, people of East Asian descent tend to under-secrete insulin. That means their pancreas simply doesn’t produce as much insulin overall, and often can’t keep up with the body’s demands—especially after eating.
Because insulin is your fat-storage hormone, not making enough of it means they’re less likely to struggle with weight gain. But here’s the catch: they can still be insulin resistant and develop prediabetes or Type 2 diabetes at much lower body weights. In fact, many East Asians store more visceral fat—the dangerous kind that wraps around organs—even if they appear slim on the outside.
They also tend to have lower levels of IGF-1 (a growth factor similar to insulin), which is linked to shorter stature but also longer lifespans and lower cancer risk.
So if you’ve ever wondered why someone can be thin, eat tons of rice and noodles, and still develop diabetes—this is why. It’s not that rice and noodles are magically healthy. It’s that their pancreas can’t keep up. That’s why you’ll often see diabetes in East Asian populations—even in those who appear thin.
South Asian and Middle Eastern Populations
South Asians have some of the highest rates of insulin resistance and Type 2 diabetes, even at a young age and at much lower BMIs.
They’re genetically predisposed to central fat storage (more fat around the organs), which is much more dangerous than subcutaneous fat. This visceral fat is highly inflammatory and contributes to early insulin resistance, metabolic syndrome, and even cardiovascular issues.
Many South Asians also have a strong tendency to over-secrete insulin—especially in response to starch and sugar. This makes their traditional diets, which are often rich in white rice, potatoes, lentils, roti, and dairy, particularly problematic. When you combine that kind of insulin-spiking diet with a genetic predisposition toward elevated insulin levels, it creates the perfect storm for metabolic dysfunction.
This helps explain why South Asian women with PCOS often struggle more severely with symptoms like obesity, acne, hirsutism, acanthosis nigricans, and hair loss. These aren’t random issues—they are all driven by high insulin. And in a population already prone to overproducing insulin, the impact is even more intense.
Middle Eastern Populations
Middle Eastern populations, like their South Asian counterparts, often have a cultural diet that’s rich in starch-heavy staples: white rice, pita, flatbreads, lentils, potatoes, and sweetened dairy. These foods, while deeply woven into tradition, are also highly insulin-spiking—especially when eaten together and frequently throughout the day.
Genetically, many individuals of Middle Eastern descent tend to over-secrete insulin, especially in response to starches and sugars. This makes the traditional diet particularly problematic, as it keeps insulin levels high all day long. Over time, this chronic elevation of insulin drives fat storage, inflammation, irregular cycles, and higher risk of PCOS, Type 2 Diabetes, and cardiovascular disease.
You may often hear people say, “But everyone in my family eats this way!” That may be true—but your genetic makeup means your body processes those foods differently.
And here’s something important to understand: many Middle Eastern women struggle with weight, fatigue, skin issues, or irregular periods and are told “everything is normal.” But under the surface, insulin is silently driving hormonal imbalance.
Indigenous Populations (Native American and First Nations)
Indigenous populations have some of the highest rates of diabetes in the world—not because of poor choices or lack of willpower, but because of a massive mismatch between their genetics and today’s food environment.
Even historically, when starch-heavy foods like corn were introduced, it didn’t go well. It’s well-documented that corn caused widespread tooth decay in tribal populations—because their bodies simply weren’t used to handling that much glucose. That alone should have been a clue.
Today, the traditional low-starch, low-sugar way of eating has been replaced with ultra-processed foods, and these populations are paying the price. The problem isn’t the people—it’s the food. Their bodies were never meant to handle this kind of diet, and it’s showing up as diabetes, heart disease, PCOS, and more.
European Populations
European ancestry tends to fall somewhere in the middle. Historically, many Northern Europeans adapted to dairy consumption (thanks to the lactase persistence gene) and developed more mixed metabolic profiles—some under-secreting insulin, some over-secreting depending on the region and diet.
Starch, alcohol, sugar, and a sedentary lifestyle still wreak havoc here—but in general, people of European ancestry tend to develop insulin resistance later in life. That is, unless they have PCOS. Then all bets are off.
Hispanic Populations: Split Into Two
Latino Ancestry (Central and South American Indigenous roots):
Latino individuals with Indigenous ancestry often carry the same thrifty genes that allowed their ancestors to survive food scarcity. That means their bodies are wired to hold onto calories and store fat—especially considering their high starch diets.
They’re more likely to have higher baseline insulin levels, insulin resistance, and metabolic syndrome at younger ages. Diets high in starches like rice, tortillas, corn, and beans only make this worse. These foods may be cultural staples, but that doesn’t mean they’re a good fit for your metabolism.
European Hispanic Ancestry (e.g., Spanish):
Those with mostly European ancestry may share more of the metabolic traits common in other European groups. However, the introduction of more starch and sugar into modern Hispanic diets has increased the metabolic burden across the board—regardless of ancestral breakdown.
What Does This Mean for You?
No matter your background, you can’t out-genetics a modern diet.
Remember, you can’t look at what someone else eats and assume it will work for you. If your body tends to oversecrete insulin, a high-starch diet will lead to weight gain, no matter how “healthy” it seems. On the flip side, if you undersecrete insulin, you might stay lean but still struggle with blood sugar issues and poor metabolic health. It’s not about copying someone else’s plate—it’s about understanding your own biology and working with it, not against it.
References
Goedecke JH, et al. Pathophysiology of type 2 diabetes in sub-Saharan Africans. Diabetologia. 2022. Read more
Mohan V. Lessons Learned From Epidemiology of Type 2 Diabetes in South Asians: Kelly West Award Lecture 2024. Diabetes Care. 2025. Read more
Lee J, et al. Evolving Characteristics of Type 2 Diabetes Mellitus in East Asia. Endocrinol Metab. 2025. Read more
Aguayo-Mazzucato C, et al. Understanding the growing epidemic of type 2 diabetes in the Hispanic population living in the United States. Diabetes Metab Res Rev. 2019. Read more
Hasson BR, et al. Racial/Ethnic Differences in Insulin Resistance and Beta Cell Function: Relationship to Racial Disparities in Type 2 Diabetes among African Americans versus Caucasians. Curr Obes Rep. 2015.
