Crash Diets May Temporarily Raise Heart Fat Levels
Crash diets, sometimes called meal replacement programs, can cause a temporary deterioration of heart function according to a recent study.
The study enrolled 21 obese individuals with an average age of 52 years. They consumed just 600 to 800 kcal every day for eight weeks. Each participant underwent an MRI at the study’s start, one week into the study, and at eight weeks.
The MRIs revealed that after one week total body, visceral, and liver fat had diminished significantly. There were also substantial improvements in insulin resistance, glucose, blood pressure, fasting total cholesterol, and triglyceride levels.
Yet, not all the findings were immediately positive. After the first week, fat content in the heart was elevated by 44 percent and correlated with a decline in heart function, though this condition was transient.
By eights weeks, heart function and fat content were better than before the diet began. The other measurements continued to improve as well.
“The metabolic improvements with a very low calorie diet, such as a reduction in liver fat and reversal of diabetes, would be expected to improve heart function. Instead, heart function got worse in the first week before starting to improve,” said aid researcher Dr. Jennifer Rayner, clinical research fellow, Oxford Centre for Magnetic Resonance, University of Oxford, Oxford, UK.
The researcher explained that a sudden reduction in calories releases fat from different areas in the body. The fat enters the bloodstream and temporarily swamps the heart muscle. The impact of this temporary rise in heart fat needs further study since it could exacerbate any existing heart conditions.
However, low calorie diets can be beneficial for weight loss, lowering blood pressure, and reversing diabetes. “If you have heart problems, you need to check with your doctor before embarking on a very low calorie diet or fasting. People with a cardiac problem could well experience more symptoms at this early time point, so the diet should be supervised,” says Dr. Rayner.
Source: European Society of Cardiology
Photo credit: Tom Sens