Most of us know too much sugar is bad for our health. But is there a link between eating too much sugar and fertility? Possibly. 

According to studies, consuming large amounts of added sugar, particularly from sugary drinks, can lead to health problems that can negatively affect fertility. While more research is needed to confirm the sugar-fertility connection, limiting your sugar intake supports health.¹

And by following a nutritious fertility diet and reducing sugar intake, you are improving your overall health, and in turn, supporting your body’s ability to conceive.²

Keep reading to learn what the research says on sugar and fertility, how much sugar is too much, tips for limiting sugar, and what healthier sugar alternatives are out there.

How Sugar May Impact Fertility

Based on what is known so far, it appears that there is more of an indirect relationship between high sugar intake and decreased fertility rates. 

This means that the negative effects of too much sugar such as insulin resistance, impaired semen quality, weight gain, and inflammation may be the potential risk factors for infertility.³

Regarding sugar and fertility, we are specifically referring to the added sugar in sugary drinks and food products, not the natural sugar found in whole grains, starchy vegetables, or fruits.

Insulin Resistance

While insulin resistance is more common in polycystic ovary syndrome (PCOS) specifically, eating too much sugar over time can also increase insulin resistance in anyone.⁴

In one study of women with PCOS, insulin resistance was associated with lower IVF implantation rates.⁵ The researchers in this study suggested that insulin resistance may negatively affect endometrial function, the layer of tissue that surrounds the uterus, reducing the success of the treatment.

Semen Quality

Just like women, male fertility is affected by many factors as well, including sugar intake. 

One recent study showed excess sugar consumption was associated with reduced sperm concentration in men. A significant decrease in concentration was seen both from consuming sugar from soft drinks and sugar in food products.⁶

The soft drink consumption in this study was not excessive, averaging only 0.2 drinks per day, but it still reduced sperm concentration between 18-23%.

Weight Gain

Too much added sugar in the diet can lead to weight gain and increased fat storage in the body.⁷ While a modest amount of weight gain may be beneficial for fertility if you are considered underweight, gaining weight by eating more sugar is not the ideal way to do it. 

Instead, you can best support your fertility by gaining weight with a healthy, calorie-dense diet if you are underweight. 

Sugar Intake Recommendations for Fertility

How much sugar is considered too much? Is any amount okay? At this point in time, sugar recommendations for fertility are essentially the same as the guidelines for the general population. 

Added sugar is the biggest culprit, so it is important to look for this on the nutrition label. It will typically be under the “total sugars” line and is separate from the “total carbohydrates.”

If you’re trying to conceive, it’s best to limit sources of added sugar as much as possible.⁸

Natural Sugar vs. Added Sugar

When it comes to fertility and sugar intake, the natural sugar found in whole foods is not a concern. For example, the fructose found in fruit, lactose found in cheese, or the complex carbs in whole grains like whole-wheat bread or quinoa are all healthy, natural sugars.

The added sugar sources to pay attention to include sugary beverages like sweetened coffees and lattes, soda, juice, alcohol, energy drinks, flavored yogurt, refined cereals, packaged oatmeal, sweets, and pastries.

Tips for Limiting Sugar

The best way to curb your added sugar intake is by limiting processed foods, sweets, and sugar-containing beverages of any kind. Of course, this may sometimes be easier said than done, as sugary foods may feel comforting during your fertility journey.

Luckily there are some simple swaps and ways to lower your added sugar intake.

1. Wean yourself off slowly – If you’re used to a lot of sugar, your taste buds need time to adjust to cutting back. Start small by reducing the amount of sugar in your coffee or replace one sweet treat with fruit so you don’t feel deprived.

2. Swap your coffee sweetener – Instead of sugar in your coffee or tea, try stevia or monk fruit. These are two natural sweeteners that do not appear to negatively impact blood sugar levels.⁹

Also, be mindful of any flavored coffees, flavored coffee creamers, or fancy lattes at your favorite coffee shop that likely contains added sugars. It’s best to choose a traditional coffee with healthier sweeteners like monk fruit or stevia, if needed.

3. Enjoy naturally sweet foods – Eat more foods that are naturally sweet, like fruit or sweeter vegetables such as sweet potatoes. Doing this more regularly can satisfy a craving for sweets in a much more nutritious (and satisfying) way. 

4. Try plain yogurt – Plain yogurt is significantly lower in sugar than flavored yogurt, and still packs all of the same nutritional benefits. If you need more sweetness, stir in some fresh fruit like blueberries, strawberries, or grapes.

5. Use steel-cut oats – Oatmeal can be incredibly nutritious, but the flavored pre-made versions can be loaded with added sugar. They also are more heavily processed, and so likely won’t hold you over nearly as long as the hearty steel-cut version. 

Try making steel-cut oats instead and add a sprinkle of cinnamon and fruit for natural sweetness (and more steady energy).

6. Swap your beverages – Instead of soda or juice, you can try sparkling water with lemon or lime.

7. Enjoy healthier sweets – Instead of cookies or other sweets at night, try one bite of dark chocolate or a small handful of dark chocolate almonds. Frozen fruit with a dollop of whipped cream is also a yummy option.

These options satisfy a sweet craving, but with much less added sugar.

Conclusion

While indirect, there is a definite link between sugar and fertility for both men and women. 

There are still unanswered questions, and more research is needed to confirm how much of an impact sugar plays in fertility outcomes.

Based on the available research, lower is better and it’s best to stick to a general recommendation of a maximum of 6 teaspoons of added sugar per day for women and 9 teaspoons per day for men. 

Always speak to your doctor and registered dietitian to determine what amount of sugar is safe for you, and how it fits into your overall fertility plan.