The so-called health authorities have been promoting a low-fat, high-carbohydrate diet for decades now. Yet infertility rates are higher than they’ve ever been before – and still rising. 1 in 7 women already have trouble conceiving, and a recent study in the UK predicted that number could rise to 1 in 3 by the year 2020.
The following three arguments suggest that a high-fat – not a low-fat – diet is optimal for fertility and pregnancy.
Breast milk is the perfect food for infants
Human breast milk is undoubtedly the perfect food for human infants. The nutritional composition of human breast milk has evolved over 2.5 million years to supply the exact ratio of nutrients necessary for proper growth and development.
What is that ratio?
Human breast milk is 55% fat, 38% carbohydrate and 7% protein by calories. Breast milk, therefore, is high in fat, moderate in carbohydrate and low in protein. Logic dictates that the ideal diet for women attempting to get pregnant and those that are already pregnant or breastfeeding would have a roughly similar macronutrient breakdown.
Fat is the preferred energy source of the body
The lean human body is 74% fat and 26% protein by calories. Fats are a structural part of every human cell and the preferred fuel source of the mitochondria, the energy-burning units of each cell.
The human body stores energy from food for future use as saturated fat, which is a cleaner burning fuel source than glucose. Unlike glucose, saturated fat isn’t toxic to the body in high doses.
Contrary to popular belief, our bodies are designed to run on fat – primarily saturated. If we give it the right fuel, it functions well. If we give it the wrong fuel, it will still run, but not as well. And it will be far more likely to break down.
Omnivorous animals naturally prefer and thrive on a high-fat diet
Animals instinctively eat a mix of foods that is healthy. They don’t have diet gurus and the internet to confuse them. When scientists let mice (omnivorous animals) choose from an unlimited supply of fat, protein and carbohydrates, mice naturally choose to get 85% of calories from fat. Yet none of these mice get fat!
Keep in mind there’s a wide variety of macronutrient ratios in healthy populations around the world, and there’s plenty of room for individual variation too. Some people naturally need or tolerate more or less fat, carbohydrate and protein than others.
But the key in the context of fertility and pregnancy nutrition is to get a significant percentage of calories from fat.
Why is fat so important for fertility and pregnancy?
Saturated fat is especially beneficial for fertility. A study at Harvard found that women who ate two or more servings of low-fat or non-fat dairy per day, like skim milk or yogurt, had 85% higher risk of infertility than those that ate full-fat dairy products.
Another study found that women who eat less saturated fat have a smaller chance of becoming pregnant. More specifically, the authors found that women with oligomenorrhea, a condition of light or infrequent menstruation associated with infertility, consume significantly less saturated fat and significantly more polyunsaturated fat than women with normal menstruation and fertility.
Polycystic ovary syndrome (PCOS) is the #1 cause of infertility in women in the U.S. PCOS is characterized by insulin resistance and testosterone dominance, a hormone imbalance that is often caused or made worse by a low-fat, high-carbohydrate diet. Why? Because high-carb diets can promote insulin resistance, which in turn converts estrogen into testosterone.
Dr. Michael Fox, a reproductive endocrinologist in Florida, has had great success treating women with PCOS with a high-fat, low-carbohydrate diet. Before he switched to this approach, almost all of his patients needed drugs or IVF, or both, to become pregnant. Since he started using a low-carb diet with these patients, fewer have needed drugs and very few have needed IVF.
High-fat diets improve male fertility too
Eating too many refined carbohydrates like white flour or sugar can promote insulin resistance. In men, however, insulin resistance has the opposite effect than it has in women: it causes the conversion of testosterone into estrogen.
This is problematic because testosterone plays several important roles in male fertility. It’s essential to the development and maintenance of male sexual organs, and to the production, motility and volume of sperm.
But isn’t fat bad for me?
Contrary to popular belief, fat isn’t your enemy.
Over the last 50 years we’ve been brainwashed to believe fat is bad for us. We’ve been told it makes us fat, raises our cholesterol and gives us heart disease.
But both anthropological research and clinical studies have revealed this is false, and the low-fat, high-carbohydrate diet promoted by groups like the American Heart Association has been a spectacular failure. Rates of obesity, diabetes and heart disease are still skyrocketing higher each year.
This is a huge subject we could easily devote an entire book to. In fact, many books have been devoted to it! For more information, I’d recommend reading Eat Fat, Lose Fat, by Mary Enig & Sally Fallon, and Why We Get Fat and What To Do About It, by Gary Taubes.
In the meantime, I’ll cover the main points here.
First, eating fat doesn’t make you fat. If that were true, high-fat, low-carb diets like Atkins wouldn’t be superior to low-fat diets for weight loss – and they are – and traditional peoples like the Inuit (who get up to 90% of calories from fat) and the Masai (who get between 60-70% of calories from fat) would be fat – and they’re not.
Instead, it’s the over-consumption of processed and refined carbohydrates like breads, bagels, crackers, cookies, chips, etc. along with industrial seed oils that have made us fat and have contributed to ever-rising rates of obesity and diabetes.
Second, eating saturated fat doesn’t cause heart disease. There are two parts to this hypothesis: A) that eating saturated fat raises cholesterol levels in the blood, and, B) that high cholesterol levels in the blood cause heart disease.
It turns out that both parts of this hypothesis are incorrect.
Recent reviews of the scientific literature show that eating saturated fat and cholesterol does not raise cholesterol levels in the blood in most cases, and even if it did, high cholesterol alone does not cause heart disease.