4 Biomarkers you can improve with lifestyle changes

Upgrading your habits can pay dividends for your cardiovascular and metabolic health.

WRITTEN BY

Julie Stewart

Updated: 01/12/2026|10 min read

While some medications, such as statins, can be incredibly effective at lowering particular blood markers, not every out-of-range result requires a pill. For some, your doctor may recommend lifestyle changes before considering medication.

Although results can vary based on your genetics and health history, cleaning up your diet, exercising more, or adjusting other habits could dramatically improve some of your health markers in just a few weeks.

Research suggests that lifestyle changes can influence insulin, hemoglobin A1C, LDL (and often ApoB) cholesterol, and blood pressure more than other biomarkers. Learn evidence-based strategies to improve your levels, how quickly you could see shifts, and how much these markers can change.

This information is only for educational purposes and does not constitute medical advice. Your doctor knows you best; talk to them about your personal lab results.

Which health markers respond most to diet and exercise changes?

Although there’s no “best” nutrition and physical activity plan for everyone, research consistently shows the benefits of favoring whole, plant-based foods over processed ones and moving more throughout the day. These upgrades can lead to significant changes in a few key biomarkers.

Insulin

Insulin is a hormone that regulates blood sugar and acts on key organs, such as the brain, heart, kidneys, bones, and skin. High insulin levels often signal insulin resistance, where your cells don’t respond to insulin’s signal to take up blood glucose, which can lead to Type 2 diabetes. Studies show that following a healthy diet or an exercise plan can reduce fasting insulin (a marker of how well your body processes blood sugar). Multiple diets and activity types have shown effects.

For example, a plant-forward eating style can reduce fasting insulin by about four microunits per milliliter (µU/mL) in trials lasting at least 14 days, according to a recent review of eight randomized controlled studies. (Many experts advise keeping insulin levels below 10 µU/mL.)

Intermittent fasting—or restricting food intake during specific periods of the day or certain days of the week—also shows benefits. A review of 10 randomized controlled trials found that people with insulin resistance who practiced intermittent fasting for anywhere from 7 days to 12 months reduced their fasting insulin by an average of 13.25 µU/mL, suggesting increased insulin sensitivity.

Exercise can help your body use insulin more effectively, too. A new review of studies found that a wide variety of activities—but especially resistance training, cycling, and running—improved fasting insulin levels. Participants worked out about 3 to 10 hours per week for two to 26 weeks.

Whatever workout routine you start, be sure you can stick with it: Eight weeks of aerobic training can decrease fasting insulin by almost 2 µU/mL, but four weeks wasn’t enough to show results in new research.

How fast this marker can move: Two to eight weeks

Why does it move? Low-calorie, antioxidant-rich plant foods might shift your gut bacteria profile to improve insulin sensitivity. Gut bacteria may affect insulin regulation by reducing intestinal inflammation and influencing how the gut metabolizes food and produces glucose. And research suggests intermittent fasting improves insulin function by shifting the balance of leptin and adiponectin, two hormones linked to hunger and metabolism. This holds whether or not IF leads to weight loss. Reducing high-carb foods also reduces the body’s need for insulin to clear high blood sugar loads.

As for exercise, as you contract your muscles, they become increasingly sensitive to insulin signaling and efficient at using glucose without insulin, decreasing the need for your beta cells to produce more. Resistance training helps you build muscle mass to use glucose; cycling works large muscle groups that are high in type-1 muscle fibers, which are rich in glucose-transporting proteins; and running can help, in part, by burning glucose stores in muscles.

How might individual results vary? People don’t all respond to insulin the same way. Genetics, body composition, and lifestyle history create different baselines of insulin sensitivity, which explains why the same diet can yield various outcomes. One study found that people at higher genetic risk for diabetes improved insulin sensitivity on a diet with ~25% of calories from protein, while those at lower risk did better with ~15% of calories from protein. This suggests protein intake may interact with genetic risk, but the broader takeaway is that natural differences in insulin sensitivity shape individual results.

Another area where more research is needed, though promising: A recent rodent study suggests exercise might help offset a genetic tendency toward insulin resistance.

Hemoglobin A1C

Hemoglobin A1c (HbA1C) measures your average blood sugar level over the last two to three months based on how many of your red blood cells have a glucose molecule attached. High hemoglobin A1c is a sign of prediabetes or Type 2 diabetes. Studies show that a one-two punch of a low-calorie diet and an exercise regimen can reduce HbA1C.

Several eating styles may help. A study review of 42 studies suggests that low-carbohydrate, ketogenic, and low-fat diets can reduce HbA1c by 0.69%, 0.73%, and 1.82%, respectively. Another meta-analysis indicates that the Mediterranean Diet, which is rich in whole foods like vegetables, fruit, whole grains, extra-virgin olive oil, and nuts, can reduce HbA1C by 0.39%. These shifts may seem small, but remember that an HbA1C of 5.7% to 6.4% indicates prediabetes, and an HbA1C of 6.5% or higher indicates diabetes. So, depending on your levels, a 0.5% decrease could change your diagnosis.

Adding physical activity may enhance this positive effect. In a recent randomized controlled trial, 169 adults with Type 2 diabetes ate a whole-food, plant-based diet and exercised 30 to 60 minutes a day. After 12 weeks, their HbA1C decreased 1.3%, and after 24 weeks, HbA1C fell another 0.7%. Nearly a quarter of people who followed this protocol returned their HbA1C to normal.

Any workout is better than none. A recent meta-analysis of 158 studies showed that, compared to a control group that didn’t exercise, all types of exercise were associated with lower HbA1c. High-intensity interval training reduced HbA1c the most (0.61%), followed by aerobic training (0.58%) or a combination of resistance and aerobic training and resistance training (0.4%).

How fast this marker can move: 8-12 weeks

Why does it move?

HbA1c rises when your average blood sugar rises, which happens most clearly when you eat a lot of fast-digesting carbs and added sugars. Diets that emphasize fiber-rich, slowly digested carbs help smooth blood sugar swings, keeping HbA1c lower. Beyond carbs, fat quality also matters: replacing saturated fat with polyunsaturated fat may reduce oxidative stress and improve insulin sensitivity, both of which support lower HbA1c. Together, these shifts explain why whole-food, plant-rich eating patterns consistently move this marker in the right direction.

Meanwhile, exercise helps your muscles better transport and use glucose. As you increase the intensity of your workouts, blood sugar control increases.

How might individual results vary? Insulin variability also affects HbA1c, as it controls how quickly glucose is cleared from the bloodstream and thus overall levels. In addition, the same factors—genetics, body composition, gut microbiome—all create individuality in glucose control. Finally, we also know there are group dynamics. Men tend to have higher hemoglobin A1c levels than women, research suggests, perhaps because of lower hemoglobin levels due to red blood cell turnover during menstruation. And one review of 30 studies found that diet and exercise interventions reduced HbA1C in White and Asian study participants but not Black or Hispanic participants. The researchers say genetics, insurance coverage differences, or behavioral, social, or nutritional factors might explain these results.

LDL cholesterol

In excess, low-density lipoprotein (LDL) can accumulate in your arteries, increasing your cardiovascular risk. In one study, a diet high in nuts, soy, soluble fiber from foods such as legumes and eggplant, and plant sterols (often consumed via fortified foods or supplements) reduced LDL by an average of 28 milligrams/dL (mg/dL) in three weeks. Another review suggests that aerobic exercise, or a combination of aerobic and resistance training, can reduce LDL by about 7 mg/dL within three weeks to a year (12 weeks was the average).

How fast it can move: Three weeks to one year

Why does it move? LDL cholesterol rises most predictably with higher intake of saturated fat. Saturated fat reduces the number and activity of LDL receptors in the liver—the central “clearance system” for LDL particles. With fewer receptors pulling LDL out of circulation, more of it lingers in the blood. Diets high in fiber-rich, plant-based foods not only reduce saturated fat intake but also help clear LDL through binding in the gut. Polyunsaturated fats add another benefit by enhancing receptor activity and improving how cholesterol is packaged and transported. Meanwhile, strength and endurance exercise might boost the function of high-density lipoprotein (HDL), allowing it to sweep more LDL away.

Because every LDL particle carries exactly one molecule of apolipoprotein B (ApoB), higher LDL levels also mean more ApoB. And since ApoB reflects the total number of atherogenic particles (not just how much cholesterol they’re carrying), many experts now consider it an even more precise risk marker than LDL itself.

How might individual results vary? If you have familial hypercholesterolemia—a genetic condition that makes it harder to clear cholesterol—lifestyle changes alone might not be enough to maintain normal LDL. There’s significant individual variability in how much diet affects this biomarker. In a recent study of healthy men who replaced saturated fats with unsaturated fats, their cholesterol levels explained about a third of the variation in LDL reduction before starting the diet and how well they followed the diet. In an earlier study, genetics reduced the LDL-lowering impact of a low-fat diet by only 4 percent. Overall, more research is needed to determine other genetic and metabolic variations. In addition, research suggests exercise could help offset the effects of an LDL-raising genetic variant.

Blood pressure

When you have high blood pressure, blood pushes too hard on the walls of your arteries. Over time, this pressure can damage your blood vessels and organs, leading to complications such as heart attacks, strokes, kidney problems, and dementia. Low-sodium, whole-food diets can reduce high systolic blood pressure—the top number—by up to 4.6 points within 1 to 5 months. Meanwhile, you could reduce your systolic BP by 7.2 points and diastolic BP by 5.6 points by completing 150 minutes of aerobic exercise weekly over four to 52 weeks, research suggests.

How fast it can move: One month to one year

Why does it move? Blood pressure reflects the force of blood against your artery walls, and it shifts with changes in both fluid balance and vessel function. Eating lots of salty, processed foods increases sodium levels, which makes your body retain water and raises blood volume — pushing pressure higher. Diets rich in potassium (think fruits, vegetables, legumes) counteract this by helping your kidneys excrete sodium and relax blood vessel walls. Excess body weight, alcohol, and inactivity also stiffen arteries and increase the heart's workload, while regular exercise and plant-rich diets improve vascular elasticity and reduce vascular resistance. These changes explain why cutting sodium, managing weight, and boosting potassium intake consistently lower blood pressure.

How might individual results vary? Genetics explains about 20 percent of the population’s variation in high blood pressure. However, research suggests healthy lifestyle factors improve blood pressure regardless of underlying genetics.

What other lifestyle factors can dramatically shift health metrics?

While diet and exercise are often the starting points, adopting a few more new habits—or ditching old ones—can also help you transform your health markers.

Losing weight

If overweight or obesity is a factor, losing weight through diet and exercise has added benefits for improving insulin sensitivity, HbA1C, LDL cholesterol, and blood pressure. Weight loss also lowers alanine aminotransferase (ALT), a liver enzyme that helps your body break down food. Obesity can elevate ALT, signifying an increased risk of fatty liver disease. In a review of studies, every kilogram (2.2 pounds) of weight loss led to a 0.83-unit drop in ALT. (ALT typically ranges from 7 to 55 units per liter for males and 7 to 45 units per liter for females.)

Drinking less

When heavy drinkers stop drinking, their levels of the liver enzyme gamma-glutamyl transferase (GGT) drop by 19 percent in 12 weeks. GGT helps protect cells from alcohol’s effects, but in high amounts, it’s linked to elevated risks of heart disease and other poor health outcomes. Even in moderate drinkers, one alcohol-free month can reduce GGT by 14 percent. When heavy drinkers stopped for a month, their levels of the liver enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT) dropped by 9 percent and 20 percent, respectively. When elevated, both enzymes can signal liver damage.

In moderate to heavy drinkers, teetotaling for a month also reduces HOMA-IR, a marker of insulin resistance, by 26 percent. More research is needed to explain the link between drinking and insulin function, the researchers say. However, they suspect weight loss from drinking less is not the sole explanation.

Also, within days of going sober, levels of inflammatory cytokines decrease, and anti-inflammatory cells increase.

Quitting smoking

Quitting smoking can reduce blood pressure by five points within three months. One reason: The nicotine in cigarettes increases blood pressure by triggering the release of the hormones epinephrine and norepinephrine, researchers say. Quitting smoking also improves lung function by 5 percent, measured by forced expiratory volume (how much air you exhale per breath).

Managing stress

The stress hormone cortisol dials up when we’re overwhelmed, harming cardiovascular, metabolic, and immune health. Fortunately, stress-busting habits can quickly reduce cortisol levels. For example, 30 minutes in nature can reduce salivary cortisol by 10.6 percent.

Over time, consistent meditation and movement can bring lasting benefits. In a study of women with Type 2 diabetes, aerobic training combined with slow-breathing exercises and mindfulness meditation reduced cortisol levels by 30%. Deep, rhythmic breathing calms the sympathetic nervous system to promote relaxation, the researchers say.