Why are trans fats bad for men's and women's fertility?

What are trans fats? Why are trans fats bad if you are trying to conceive? Learn how this poison is threatening our health and reproductive systems!

why are trans fats bad hot fries No trans fat! Firstly, lets explain what they are... Trans fats (also called trans fatty acids) are either monounsaturated or polyunsaturated fats which have been altered by way of partial hydrogenation to become semi solid.

Why are trans fats bad? Because this type of fat is so unnatural that it shouldn't be classed as a food!

A harsh solvent is used, along with a metal catalyst (such as nickel) to react with the hydrogen gas (chemical reaction). This is then forced into the liquid oil at high temperatures. This process of adding hydrogen atoms changes the shape of the oil molecules. The oil is then finished off by being bleached and deodorized. Yuck, doesn't sound like something edible does it!

There's another class of natural trans fats that occur in trace amounts in meats and diary produce from ruminants (sheep, cattle, or goats). This type of fat is created in the animals stomach by bacteria. Small amounts of this natural fat should not cause concern. We recommend only eating organic meats and diary where the animals have only been fed organically grown feed or grass.

why are trans fats bad candle wax History - In 1901 a German chemist named Wilhelm Normann was the first to prove that liquid oils could be hydrogenated. He then patented this process in 1902. The U.S. company Procter and Gamble took over the Normann patent in 1909. Their initial use for this fat was to replace animal tallow which was used for making candles in exchange for solidified cottonseed oil (cheap alternative)!

Eventually electricity took over and the candle market wasn’t so good any more. Somehow they decided that the hydrogenated oil looked and behaved like lard or butter, so there you have it, a brand new market (yummy)!

What are trans fats? Modified candle wax!

From then on, partially hydrogenated fats increased in popularity throughout the western world, until eventually they overtook the conventional use of animal fats. Rationing and the availability of this product during food shortages helped promote this new inexpensive oil. Why are trans fats bad? Because they were believed to be healthier, as they are made from vegetable oils rather than animal based products (little did they know)!

Partially hydrogenated oil tastes good as it holds onto flavor, and the smooth texture and higher melting point make it good for baking. The lower production costs and longer shelf life makes these oils very attractive for commercial manufacturers. Therefore trans fats are now widespread and commonly used in processed foods around the world.

What are trans fats found in?

♦ Partially hydrogenated cooking oils (must look at labels)!

♦ Commercially processed foods - may be present in breakfast cereals, crackers, potato crisps, popcorn, margarine, dressings, sauces, and ice cream (to name just a few).

♦ Baked goods - such as donuts, pastries, biscuits, cakes, pies, muffins, or confectionery.

♦ Fast foods - these can be extremely high in trans fats (medium fries may contain 7 grams)! Some food chains are now swapping to trans fat free cooking oils.

Difference between fully and partially hydrogenated oil

Are fully hydrogenated oils just as bad? The process of fully hydrogenating vegetable oils results in a totally different molecule structure than the partially hydrogenated oils. Strangely, this resulting product has next to no trans fat. This fat is more solid, so it's not so widely used as the semi solid version.

Why are trans fats bad for us?

Unfortunately these artificial fats have absolutely no nutritional value (unlike other fats) and only cause harm to us. These manufactured fats are a foreign substance that the body can't recognize or use!

Including natural fats in our diet is essential for our health (in the appropriate amounts of course)! All our cell membranes contain fat and we need it for the formation of our hormones (chemical messengers). This includes our reproductive hormones! Natural fats are used for tissue repair, transporting vitamins around the body, protecting our organs, and maintaining healthy skin. The human brain is made up of 60% fat (yes really)! Fat and the reproductive system are closely connected. If you haven’t already done so, read up on recommended body weight and find out why.

why are trans fats bad fried donuts

Why are trans fats bad? Because they clog up the space that the natural fats should occupy! It then becomes difficult for essential nutrients to pass in and out of cells, therefore the inter-cellular communication is disrupted. All bodily functions can be altered by these artificial molecules entering our system (scary)!

When we consume natural fats it takes the body 18 days to metabolize half of them. Why are trans fats bad? Because when we consume trans fats it takes the body 51 days to metabolize half of them! It's estimated that if a person eliminates all trans fats out of their diet, it will take approximately two years for their system to get rid of all the residual trans fat in their bodily tissues. No wonder the rates of obesity and disease have sky rocketed!

The American Heart Association recommends that only 1% of your daily calories should come from trans fats. For example if you consume 2,000 calories a day, less than 20 of those calories should be trans fats (under 2 grams).

Why are trans fats bad? Because they are all around us! The U.S. Food and Drug Administration states that the average American consumes 5.8 grams of trans fat per day (2.6% of daily calories)!

Trans fats are killers! Consumption of trans fats increases our risk of developing coronary heart disease by raising levels of bad cholesterol (LDL) and lowering levels of good cholesterol (HDL).

This artificial fat has also been implicated with links to -

  • Infertility (male and female)
  • Miscarriage
  • Low birth weight
  • Pre-eclamspsia
  • Obesity
  • Insulin resistance
  • Diabetes
  • Immune dysfunction
  • Inflammatory problems
  • Multiple sclerosis
  • Chrohn’s disease
  • Breast cancer
  • Asthma
  • Psoriasis
  • Liver dysfunction
  • Alzheimer's disease
  • Possibility of other potential health problems


Why are trans fats bad? Because research is suggesting that trans fats are having a huge effect on our sexual health. Reproductive hormonal pathways can become blocked or altered, leading to an array of fertility problems. Although there's been more research done towards the link between trans fats and female infertility, all evidence so far is also implicating this fat with lowered sperm count and quality.

Why are trans fats bad for male fertility?

Male sperm counts have been significantly dropping over the years (it's a fact)! Sperm cells are extremely sensitive to diet and toxins. Our modern diets consisting of processed/fast foods, lacking in essential nutrients and high in trans fats are believed to one of the major culprits. Any disruptions within the process of hormone formation (as trans fats cause) can upset the whole reproductive system. A change to a healthier diet can do wonders for a mans sperm!

Check out our page on how to increase sperm count to get a better idea of how to look after your swimmers! There are other lifestyle issues that can also help you with your chances of fathering a child.

Why are trans fats bad for female fertility?

Research - Dr Jorge Chavarro and his team of researchers at Harvard University, discovered that trans fat consumption could significantly increase women’s risk for ovulatory infertility. The team analyzed data from a U.S. Nurses Health Study which involved 18,555 healthy women. They were married and trying to get pregnant between 1991 - 1999. The findings of this study were published in the American Journal of Clinical Nutrition - January 2007, volume 85, no. 1, 231-237.

The women's results -

For every 2% increase in calories from trans fats instead of carbohydrates, the risk of infertility increased by 73%.

For every 2% increase in calories from trans fats instead of omega - 6 polyunsaturated fats, the risk of infertility increased by 79%.

For every 2% increase in calories from trans fats instead of monounsaturated fats, the risk of infertility more than doubled!

The Dr and his team also stated that trans fats could interfere with the activity of a cell receptor which is involved in inflammation, glucose metabolism, and insulin sensitivity. This too can lead towards female infertility.

Dangers of trans fats during pregnancy

Why are trans fats bad if you are pregnant? When a women is pregnant, any trans fats in her diet will be passed onto the baby through her own blood supply. Trans fats are known to interfere with our cells, so think what this may be doing to a growing new life! Most women don't realize that they are pregnant during the first few weeks. Therefore, it's especially important to avoid trans fats before, and whilst you are trying to conceive!

Research - Dr Charles J. Glueck of the Jewish Hospital Cholesterol Center in Cincinnati, Ohio (U.S.) and his team, found that eating trans fats may increase the risk of fetal death during pregnancy.

The group was examining dietary trans fat intake among women who were involved in a childhood to adulthood survey regarding cardiovascular risk factors. Researchers focused their study on 104 women who reported at least one pregnancy during the 25 - 30 year follow up. The average age of the women who were assessed were 39.5 years old. These finding were published in the Journal Fertility and Sterility - August 2008, volume 90, issue 2, pages 385-390.

This study found that the women with the lowest trans fat consumption (2.2% of total daily calories) had a 30% increased risk of fetal death.

Women who had a higher intake of trans fats (4.7% of total daily calories ) had a 52% increased risk of fetal death.

As the percentage of calories from trans fats increased, the risk of having one or more fetal losses also increased, reported Dr Glueck and his colleagues.

Earlier studies also found a link between a diet high in trans fats and increased insulin resistance. This increases the activity of plasminogen activator inhibitor (a member of the serpin family of proteins) which has been associated with fetal loss.

Research - Another study linked the consumption of trans fats with pre-eclampsia, a life threatening medical condition where a pregnant women develops hypertension (high blood pressure). Women with this condition had a 28% higher level of trans fats in their bloodstreams. Findings were published in the Gynecologic and Obstetric Investigation - 1998;46:84-87.

Why are trans fats bad? Because researchers have also linked trans fats with premature birth, and the low birth weights of babies that have reached full term.

why are trans fats bad nutritional label

Labeling laws

Check with your own countries regulations/laws regarding trans fats listings on foods nutritional fact panels - if there's such a law!

The Food and Drug Administration U.S. (FDA) made it mandatory to list trans fats levels on the nutritional fact panels on product packaging. However, trans fat servings of less than 0.5 grams per serving can be listed as 0 grams. That’s a shock if you thought you were avoiding it altogether!

Why are trans fats bad? Because you may be consuming them without even knowing, putting yourself and your family at unnecessary risk!

How to avoid trans fats

♦ Eat fresh organic foods as much as possible.

♦ Cut down on purchasing processed foods, and learn to check all labels.

♦ Avoid products that have the words trans fats, trans fatty acids, hydrogenated, partially hydrogenated, HVO, or shortening listed in the ingredients.

♦ If the label states 0% trans fat, still be cautious (especially if the product is imported).

♦ Canola/rapeseed oils also contain trans fats as a result of the processing at high temperatures. This is often thought of as a good oil.

♦ If you are dining out, you could check beforehand to see if the restaurant uses hydrogenated or partially hydrated cooking oils. Another option when dining out is to avoid the fried foods.

♦ Beware of unlabeled baking.

♦ Don’t keep re-heating the same cooking oil many times over, as this process can actually create trans fats (in small amounts). Use fresh oil each time.

♦ There are many trans fat free oils and products becoming available now, so do your homework!


What are trans fats? Chemically altered vegetable oils that have been partially hydrogenated.

Why are trans fats bad for fertility? Because they upset our body’s natural homeostatic balance, interfering with the formation of hormones, and numerous other bodily functions that can affect our reproductive systems.

Trans fats are a major cause of obesity and numerous other medical conditions.

Why are trans fats bad during pregnancy? Because these altered molecules are passed onto the developing baby through the mothers blood supply.

Health authorities worldwide recommend that trans fats consumption be reduced to trace amounts. However, it’s best if we can eliminate this poison from our diets altogether (trace amounts can easily add up). Many health experts believe they should be totally banned!

Discover the benefits of organic food. Modern agriculture is also proving to be detrimental towards our fertility health! This is interesting stuff, a must read!

Why are trans fats bad for you? Because this artificial food has made it's way into our food chain! Many of us have been ingesting considerable amounts of these partially hydrogenated oils without knowing the consequences. Remove them from your kitchen, and educate your friends and families about their dangers!

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