From the Guidelines
To improve insulin sensitivity and reduce the risk of developing type 2 diabetes, individuals should limit sodium intake to less than 2,300 mg per day, as excessive sodium intake contributes significantly to insulin resistance by disrupting normal cellular function and metabolic processes 1. High sodium levels in the diet can impair insulin signaling pathways in muscle and fat cells, reducing their ability to take up glucose from the bloodstream. This occurs because sodium overload alters cell membrane function, disrupts calcium signaling, and increases oxidative stress, all of which interfere with insulin receptor activity.
Key Considerations
- The most recent and highest quality study, published in 2025, suggests that limiting sodium intake to less than 2,300 mg per day is a valuable strategy for people with diabetes, with or without kidney disease 1.
- Reducing sodium intake can be achieved through reducing consumption of processed and ultraprocessed foods, avoiding adding salt to foods and during cooking, and encouraging people to eat more fresh foods, read nutrition labels, and use herbs and spices instead of salt for flavoring.
- Further reductions to 1,500 mg may be beneficial for those with existing insulin resistance, hypertension, or diabetes, but caution is warranted due to potential increased mortality associated with very low sodium intakes in people with diabetes 1.
Practical Recommendations
- Limit sodium intake to less than 2,300 mg per day
- Reduce consumption of processed and ultraprocessed foods
- Avoid adding salt to foods and during cooking
- Encourage people to eat more fresh foods, read nutrition labels, and use herbs and spices instead of salt for flavoring
- Gradually reduce salt to allow taste buds to adjust, combined with regular physical activity and maintaining a healthy weight, to significantly improve insulin sensitivity and reduce the risk of developing type 2 diabetes 1.
From the Research
Role of Sodium in Insulin Resistance
- High sodium intake is closely associated with the risk of cardiovascular disease, but the effect of low sodium intake on insulin resistance is not clear 2
- Additional randomized controlled trials with an adequate study period and reasonable levels of low sodium intake are needed to determine the association between low sodium intake and insulin resistance 2
Insulin Resistance and Dietary Factors
- Reducing the intake of simple sugars, especially from sweet drinks, sweets, and excessive fruit juice consumption, is recommended for insulin-resistant individuals 3
- Consuming complex, low-glycemic-index carbohydrates that are rich in dietary fiber has beneficial effects on insulin sensitivity 3
- An insulin-resistant patient's diet should be rich in whole grains and high amounts of non-starchy vegetables and raw fruit 3
- The beneficial effect of the Dietary Approaches to Stop Hypertension (DASH diet) and the Mediterranean diet has been confirmed 3
Insulin Resistance and Cardiovascular Risk
- Patients with type 2 diabetes mellitus frequently have coexistent dyslipidemia, hypertension, and obesity, and are at risk for microvascular and macrovascular disease complications 4
- Strategies to reduce the risks of microvascular and macrovascular disease are needed in clinical practice to optimize cardiovascular health outcomes for patients with type 2 diabetes 4
- Thiazolidinediones (insulin-sensitizing agents) are promising therapies for reducing cardiovascular risk in patients with type 2 diabetes 5, 6, 4
Treatment of Insulin Resistance
- Metformin and thiazolidinediones (pioglitazone and rosiglitazone) are insulin-sensitizing agents that can improve insulin resistance and reduce the risk of cardiovascular complications 5, 6
- Combination therapy with metformin and thiazolidinediones may provide complementary beneficial effects in the treatment of type 2 diabetes and insulin resistance 6