Carbohydrates: A Nutritional Insult?

In a seminar to the UGA Foods and Nutrition Department, Dr. Amy Goss began by discussing the etiology of metabolic disease and the common misconception of obesity as a root cause for theses pathologies; she stressed that obesity should be viewed as a result of a common antecedent, instead preferring to categorize it as collateral damage due to multiple factors including inflammation and hyperglycemia.

Individuals who struggle with maintaining their weight might be predisposed to being overweight or obese due to a specific genotype or phenotype they possess that is multiplied by nutritional insult. Nutritional insult is defined as a diet rich in highly processed carbohydrates, such as added sugar, wheat bread, and flour that results in subsequent spikes in blood insulin levels. Since insulin regulates body fat storage, constant large increases in insulin are likely to lead to increased deposits of fat and an increase in adipose tissue. This turns into one seemingly endless cycle because both ectopic fat and visceral fat contribute to insulin resistance. Thus, the more fat a person has means the more insulin resistant they are, so they have to increase the output of insulin which increases fat storage.

Dr. Goss’s most recent research involved comparing a low carbohydrate, high fat diet (43%CHO;18%Pro;39%Fat) to a more standard, control diet (55%CHO;18%Pro;27%Fat). It was determined that the low carb, high fat diet intervention resulted in relatively greater decrease of visceral fat and insulin secretion as compared to the control diet. Additionally, more weight loss was observed with a hypocaloric diet (500 kcal reduction) after eight weeks. However, one big limitation of these findings is that both diets had different glycemic loads. Dr. Goss was able to replicate these findings in women with Polycystic Ovary Syndrome where a low carb, high fat diet (41%CHO;19%Pro;40%Fat) resulted in decreased visceral and intramuscular fat and increased fasting glucose, insulin sensitivity, and beta-cell function, as compared to a control diet (55%CHO;18%Pro;27%Fat).

Dr. Goss finished her talk by discussing the UAB EatRight Clinic’s various diet plans that have proven effective in their patient population. These include a low carbohydrate diet, a Risk Reduction diet that is prescribed to individuals at high risk for cardiovascular disease, and the OptiFast diet which is a complete meal replacement program for individuals who need to lose at least fifty pounds. A more specific low carb, high fat diet that involved eating three eggs per day for eight weeks resulted in decreased weight, total fat, and insulin resistance as compared to controls who consumed Kind Bars.

While the jury is still out on the most effective diet plan to follow for weight loss and sustained health and wellness, it certainly seems that low carb, high fat diets are still on the table. With more corroborating research across different populations, this can potentially be an important prescription for disease prevention among normal weight adults and children of the general population (18.5-24.9 kg/m2 BMI) who are at a high risk of becoming overweight and obese.


  1. Michael Casas

    I agree here in that highly refined sugars are the ones that are harmful, especially in high quantities and when paired with low levels of physical activity. I do believe that these simple carbs might be one of the main causes of obesity and overweight. More education needs to be emphasized on nutrition and the positive and negative effects it can have on you when you exceed or fail to meet recommended guidelines.

    So you mean to say that glycemic loads in your diet have significant impact on your health? Why do you think this study’s method worked so well since fat is also bad for you? Also, elaborate more on the part about the daily egg consumption because that part is interesting.

    Like with everything, nothing is conclusive or universal so we must continue to research many diets and look at the human body as individual parts and as a whole. Also, another big factor to consider and that was mentioned here was genes. Physical activity also plays a huge role in diet and maximal functioning.

  2. Joanna Szymonik

    I agree with Dr. Goss. Obesity is the byproduct of multiple factors, most of which I believe are caused by personal behavior choices, such as dietary intake and physical activity levels over a long period of time. I know these studies only focus on the dietary part of inducing weight loss, but in a real life setting, I believe diet and exercise must be used together consistently for effective, long-term, and sustainable health. Diet alone will not producing lasting results. This is why relapse is practically inevitable. What do you think?