Crash diets are bad news for your heart


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Have you ever tried surviving on only celery and apples? This is just one of many extreme eating plans that popularise attractive benefits like instant weight loss, a decrease in blood pressure and reduced chances of diabetes. Yet, what many people are unaware of is the possibly fatal impact it might have on your most important organ – the heart.

Crash dieting basically puts individuals on a restrictive eating plan that does not allow for more than 1,200 calories per day. The plan could last from about a week to a month, making weight loss a short-term benefit. So if you are consi dering embarking on any popular meal replacement programme, read this to be aware of what goes on inside your body during the duration of the diet. 

Over at the University of Oxford, Dr Jennifer Rayner leads a team of researchers as they probe deeper into the impact crash dieting may have on our hearts. The results reveal that crash diets can cause a transient deterioration in heart function. 

They recruited 21 obese volunteers with an average body mass index of 37. The participants, who were 52 years old on average, were put on a low-calorie diet of 600 to 800 calories per day for eight weeks. 

Using magnetic resonance imaging (MRI), the researchers studied the heart, abdomen and liver of the participants at three points during the study - the beginning, after a week and after eight weeks. 

The scan results after a week revealed that the individuals had a significant drop in their total body, visceral and liver fat. They also had great improvements in insulin resistance and blood pressure. 

But here is the shocking part – it also showed that the participants’ heart fat content increased by up to 44 per cent. This caused a deterioration of their heart function which weakened the heart’s ability to pump blood. The lead author of the study attributes it to the sudden release of fat from the body that the heart uses as fuel, causing it to be surrounded by dangerous fatty deposits. 

Surprisingly, the MRI scan conducted at the end of the eight weeks revealed a marked improvement in the participants’ heart fat content and function - showing that heart deterioration during a crash diet is a temporary consequence. Nevertheless, the initial increase of fat in the heart may be life-threatening for some individuals. 

If you have existing heart issues, it is crucial that you consult your doctor before embarking on any low-calorie diet plan. 

Instead of cutting out several food groups for the sake of weight loss, sustain your fat loss in a much healthier way by sticking to a general 1,600-1,800 calories a day.