 When oral contraceptives were presented on the market at first time they enclosed much higher doses of hormones than those which prescribed today. One of the active ingredients in the contraceptive pill is estrogen. Its high dose is known to cause weight gain due to fluid retention. The fluid retention in turn causes increase in salt (sodium) retention. But for today’s studies proved that low dose oral contraceptives do not cause weight gain.
Very often people ask whether oral contraceptives increase appetite as many women gaining weight when they start taking oral contraceptives. It can be true if they raise your insulin level or also known as ‘insulin resistance’. But not all women are susceptible to ‘insulin resistance’, ‘Insulin resistance’ it is when raise your insulin level that is why not all women will gain weight when they take pills. It can be diagnosed by a doctor. And if you have it your blood insulin levels are chronically higher. And it is a cause of stops your fat cells from giving up their energy stores to let you lose weight.
Many other medications can also cause weight gain, for example such as pills for depression. Moreover, oral contraceptives are less effective in obese or overweight women. Studies have found that overweight women who take oral contraceptives have higher risk of pregnancy than women of normal weight. The reason is still not clear. But one of them is that since the hormones in oral contraceptives are soluble in fat, they dissolve in the fat of an overweight person rather than entering the bloodstream.
Also your liver helps to metabolize the hormones in oral contraceptives. If you are overweight, so the enzymes in your liver can enlarge so you metabolize the hormones in oral contraceptives much faster than normal. Today’s oral contraceptive pills enclose lower doses of hormones, so if your are overweight they could quickly become ‘burned’ up hence their effect in your body could be of a shorter duration and thereby increase your risk of becoming pregnant.
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