Oxidative Stress and Metabolic Syndrome

metabolic syndrome waist measurementExtra weight around the belly may not seem hazardous. However, a higher abdominal circumference is one of several contributing factors to Metabolic Syndrome. As a risk factor for diabetes and cardiovascular disease, Metabolic Syndrome can creep up over time. Hormones, insulin resistance, genetics, organ dysfunction, and mitochondrial dysfunction can play a role.

Lifestyle, including nutrition and exercise, are factors that contribute to Metabolic Syndrome, and are under our control. Therefore, preventing or reversing metabolic syndrome can improve both lifespan and quality of life. Diabetic retinopathy, central retinal artery occlusion, cataract, age-related macular degeneration, glaucoma, and dry eye syndrome are eye diseases with similar underlying risk factors to Metabolic Syndrome. Oxidative stress ties into all these problems. What is the science behind Metabolic Syndrome? What can you do to head it off?

What is Metabolic Syndrome?

Metabolic activity is the cornerstone of life, essential for maintaining our body’s vital functions. However, with the rise in living standards, we’ve also seen an increase in metabolic disorders. These conditions disrupt the body’s ability to convert food into energy and eliminate waste, often due to malfunctioning chemical reactions or organs like the liver or pancreas.

One prominent concern is Metabolic Syndrome (MetS), also known as “Syndrome X,” which has become a global health threat linked to modern lifestyles. MetS encompasses a cluster of metabolic abnormalities that elevate the risk of cardiovascular diseases. Metabolic Syndrome represents a doubling of the risk of developing cardiovascular disease and a 5-fold increased risk for Type 2 diabetes. 1

Unfortunately, most disorders associated with MetS lack obvious symptoms, though a large waist circumference can be a visible indicator. Elevated blood sugar levels may also manifest as increased thirst, frequent urination, fatigue, and blurred vision—signs commonly associated with diabetes.

Metabolic syndrome is diagnosed when an individual exhibits three or more risk factors: high blood glucose, low HDL cholesterol, high triglycerides, large waist circumference, and high blood pressure. The first three of these factors show up on blood tests that your doctor should order regularly. The measurement around the waist, at the top of the hip bones, should be less than 37″ for men, and 31.5″ for women. Waist circumferences above 40″ (men) and 35″ (women) indicate a substantially increased risk. Typically, those with MetS have apple-shaped bodies, carrying excess weight around their midsections.

Connections Between Metabolic Syndrome and Eye Diseases

In recent years, the link between diabetes, hypertension, and ocular conditions such as diabetic retinopathy (DR), cataracts, and glaucoma has become increasingly clear. 2 These eye conditions are major contributors to vision loss unrelated to refractive errors and are among the leading causes of blindness worldwide. 3 Diabetic Retinopathy, in particular, stands out as the most prevalent microvascular complication in diabetic patients and the foremost cause of vision loss among working middle-aged adults globally. 4 5 A common thread in these conditions is oxidative stress, which has been identified as a significant factor not only in Diabetic Retinopathy but in numerous other health issues. 6 7 Understanding these associations is crucial for preventing and managing vision loss in those affected by diabetes and hypertension.

Oxidative Stress: Villainous or Virtuous?

Oxidative stress occurs when there’s an imbalance between the production of reactive oxygen species (ROS) and the body’s ability to detoxify these harmful by-products. These ROS are normally generated during oxygen metabolism. Factors like environmental pollutants, chronic emotional stress, poor diet, and smoking can increase oxidative stress, leading to cell and tissue damage. This damage can trigger the onset of various diseases. A significant body of evidence shows that oxidative stress is involved in the development and progression of many health conditions, such as cancer, diabetes, metabolic disorders, atherosclerosis, and cardiovascular diseases. 8

Neurological Disease and Oxidative Stress

Studies have shown that metabolic disorders, such as nonalcoholic fatty liver disease (NAFLD), type 2 diabetes, impaired glucose tolerance (prediabetes), polycystic ovarian syndrome (PCOS), and hyperlipidemia, can lead to diabetic encephalopathy and atherosclerosis. 9 These conditions increase the risk of developing Alzheimer’s and coronary heart disease. 10

Oxidative stress has been linked to several neurological diseases, including Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis, depression, and memory loss. 11 12 Research has demonstrated that oxidative damage plays a crucial role in neuron loss and the progression to dementia. 13 This includes an increased risk of beta-amyloid plaque formation, commonly seen in Alzheimer’s disease patients. 14

Respiratory Disease and Oxidative Stress

Several researchers have pointed out that lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are linked to oxidative stress. These conditions are often determined by systemic and local chronic inflammation.15 16

Rheumatoid Arthritis and Oxidative Stress

Free radicals at the site of inflammation play a significant role in both the initiation and progression of rheumatoid arthritis. 17 This condition is characterized by the infiltration of macrophages and activated T cells.

Lifestyle Considerations

Lifestyle modification and weight loss should be the first steps in preventing or treating Metabolic Syndrome. 18 Antioxidants, which neutralize Reactive Oxygen Species (ROS) and other free radicals, can be obtained from fruits, vegetables, and supplements. Some of the most potent antioxidants include glutathione, superoxide dismutase, vitamins C and E, CoQ10, alpha-lipoic acid, arginine, curcumin, and other flavonoids, especially those found in colored fruits and vegetables. Ascorbic acid (vitamin C) is a water-soluble compound and a natural antioxidant. It reduces the risk of cancer by suppressing free radicals and oxidative stress. 19

Berberine and Metformin

Berberine is an isoquinoline alkaloid compound extracted from the traditional Chinese medicine Coptis chinensis. Modern research has shown that it has multiple pharmacological activities. 20 21 22 Several studies have demonstrated that berberine can lower blood glucose levels in people with type 2 diabetes. One study even found that berberine was as effective as metformin in reducing fasting blood glucose and HbA1c levels.

Recent research has shown that berberine can lower blood glucose levels, 23 improve insulin resistance, 24 improve hyperlipidemia, 25 reduce inflammation, 26 and help prevent mild cognitive impairment. 27 It also has anti-tumor properties. 28 These benefits address some of the limitations of using statins and metformin together and suggest that berberine has potential as a new first-line treatment.

Patients with dry age-related macular degeneration (AMD) may be able to stave off geographic atrophy by using metformin. According to research published in Investigative Ophthalmology and Visual Science, metformin appears to reduce the odds of developing geographic atrophy in these patients. This finding suggests that metformin, commonly used for managing type 2 diabetes, could have protective effects against the progression of dry AMD.

Recent research has shown that systemic berberine can protect against light-induced retinal degeneration by reducing oxidative stress in the retina. Mitochondrial dysfunctions, which play a crucial role in the development of retinal diseases like AMD, have also been implicated in various age-related conditions. Berberine is believed to interact with enzymes, receptors, and ion channels involved in mitochondrial functions. By helping to restore proper mitochondrial function, berberine shows promise not only for retinal diseases but also for brain disorders.

Clinical and experimental data support that chronic oxidative stress is a primary contributing factor to numerous retinal degenerative diseases, such as macular degeneration. 29 Recent research has shown that systemic berberine can protect against light-induced retinal degeneration by reducing oxidative stress in the retina.30

Mitochondrial dysfunctions have been implicated in the pathophysiology of several age-related diseases, including AMD. 31 Mitochondrial deficiency plays a crucial role in the development of retinal diseases. Berberine is believed to interact with various enzymes, receptors, and ion channels involved in mitochondrial functions. By helping to restore dysregulated mitochondrial function, berberine shows promise not only for retinal diseases but also for brain disorders. 32 33

Oxidative Stress and Free Radical-Fighting Vision Support Supplements

Berberine GT 60 vegcaps

Advanced Eye & Vision Support Formula (whole food) 60 vcaps

Dr. Grossman’s Meso Plus Retinal Support and Computer Eye Strain Formula with Astaxanthin 90 vcaps

Dr. Grossman’s Advanced Eye and Dr. G’s Whole Food Superfood Multi1 20 Vcap Combo – 2 months supply


ACG Glutathione EXTRA STRENGTH Spray 2oz.

Dr. Grossman’s Vitamin C Plant-Based Formula – 60 caps


ReVision Formula (wild-crafted herbal formula) 2 oz
– wild-crafted herbal formula for Liver (meridian) support. In Chinese medicine, the Liver energetically “opens to the eyes” to help support overall vision health.

Recommended Books

Natural Eye Care: Your Guide to Healthy Vision and Healing

Natural Brain Support: Your Guide to Preventing and Treating Alzheimer’s, Dementia, and Other Related Diseases Naturally

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