Reduced calorie, low fat diet is currently recommended diet for overweight and obese adults. Prior data suggest that low carbohydrate diets may also be a viable option for those who are overweight and obese.
Obesity remains a significant public health concern. One of the primary messages from providers and health-care organizations is to eat healthier foods with lower fat. Many in the lay press, however, have suggested that lower fat versions of foods contain more sugar. To our knowledge, a systematic comparison of the sugar content in food with lower fat alternatives has not been performed. In this study, we compared fat free, low fat and regular versions of the same foods using data collected from the USDA National Nutrient Database. We found that the amount of sugar is higher in the low fat (that is, reduced calorie, light, low fat) and non-fat than ‘regular’ versions of tested items (Friedman P=0.00001, Wilcoxon P=0.0002 for low fat vs regular food and P=0.0003 for non-fat vs regular food). Our data support the general belief that food that is lower in fat may contain more sugar.
Diets consisting of refined foods (REF) are associated with poor physical (e.g., obesity and diabetes) and mental (e.g., depression) health and impaired cognition. Few animal studies have explored the causal links between diet processing and health. Instead, most studies focus on the role of macronutrients, especially carbohydrate and fat concurrently with how processed are the ingredients. We previously showed that a REF low fat diet (LFD) caused greater adiposity and impaired motivation compared to an unrefined control (CON) diet consisting of similar macronutrient ratios (Blaisdell et al., 2014). Here we test the hypothesis that the same REF LFD adversely affects attentional processes and behavioral control relative to the CON diet. Rats with ad libitum access to the REF diet for two months gained greater adiposity than rats consuming the CON diet. Rats then completed training on a vigilance task involving pressing the correct lever signaled by a brief visual cue whose onset varied across trials. A REF diet reduced accuracy when there was a delay between the start of the trial and cue onset. Poorer accuracy was due to increased premature responses, reflecting impulsivity, and omissions, indicating an inability to sustain attention. These results corroborate the links between consumption of refined foods, obesity, and poor cognition in humans. We discuss the possible causal models that underlie this link.
Consuming a high-fat diet may result in behavioral deficits similar to those observed in aging animals. It has been demonstrated that blueberry supplementation can allay age-related behavioral deficits. To determine if supplementation of a high-fat diet with blueberries offers protection against putative high-fat diet-related declines, nine month old C57Bl/6 mice were maintained on low fat (10% fat calories) or high-fat (60% fat calories) diets with and without 4% freeze-dried blueberry powder. Novel object recognition memory was impaired by high-fat diet; after 4 months on the high-fat diet, mice spent 50% of their time on the novel object in the testing trial, performing no greater than chance performance. Blueberry-supplementation prevented recognition memory deficits after 4 months on the diets, as mice on this diet spent 67% of their time on the novel object. After 5 months on the diets, mice consuming high-fat diet passed through the platform location less often than mice on low-fat diets during probe trials on days two and three of Morris water maze testing, whereas mice consuming high-fat blueberry diet passed through the platform location as often as mice on the low-fat diets. This study is a first step in determining if incorporating more nutrient dense foods into a high-fat diet can allay cognitive dysfunction.
The relationship between primary intestinal lymphangiectasia (PIL) and liver fibrosis is an emerging topic with many obscure aspects due to the rarity of the disorder. A recent paper reported that a six-month low-fat diet improved liver fibrosis. We report the case of a 17-year-old girl affected by PIL whose hepatic fibrosis progressively worsened within one year, despite dietetic support. This and the previous case report describe extraordinary events, which do not allow clear-cut clinical aspects to be established. Nevertheless, both cases suggest that in patients with PIL, it is necessary to closely monitor liver morphology with in-depth investigations including not only ultrasonography, but also elastography.
The high consumption of low-fat and nonfat dairy products is associated with reduced risk of high blood pressure.