According to Gram Research analysis, women with gestational diabetes have thicker fat layers under their skin and more water in their bodies compared to pregnant women without the condition, even when they started pregnancy at similar weights. A 2026 cross-sectional study of 80 Polish pregnant women found that those with gestational diabetes had skinfold thickness of 21.5 millimeters versus 19.0 millimeters in controls, and 63% had a family history of obesity compared to 38% of controls. Women with gestational diabetes also made significant dietary changes after diagnosis, with 77% following a prescribed diet and 93% demonstrating greater nutritional knowledge.
A new study from Poland looked at 80 pregnant women to understand how gestational diabetes (a type of diabetes that happens during pregnancy) affects the body. Researchers compared 30 women with gestational diabetes to 50 women with normal blood sugar levels. They found that women with gestational diabetes had thicker fat layers under their skin and more water in their bodies, even though they weighed about the same before pregnancy. The study also discovered that these women were more likely to have family members with obesity or diabetes. Interestingly, women with gestational diabetes made bigger changes to their diet and knew more about nutrition after being diagnosed, which shows how the condition motivated them to take action.
Key Statistics
A 2026 cross-sectional study of 80 pregnant women from Poland found that women with gestational diabetes had significantly thicker fat layers under their skin at 21.5 millimeters compared to 19.0 millimeters in women without gestational diabetes.
According to the same 2026 study of 80 pregnant women, 63% of those with gestational diabetes had a family history of obesity compared to only 38% of pregnant women with normal blood sugar levels.
Research reviewed by Gram found that 77% of pregnant women with gestational diabetes followed a prescribed diet after diagnosis, compared to 0% of pregnant women without gestational diabetes.
A 2026 study of 80 pregnant women showed that women with gestational diabetes had higher total body water at 34.6% of body weight compared to 31.9% in women without gestational diabetes, despite similar pre-pregnancy weight.
The Quick Take
- What they studied: How pregnancy diabetes affects body fat, water content, diet choices, exercise habits, and family health history in pregnant women
- Who participated: 80 pregnant women from Poland: 30 with gestational diabetes and 50 with normal blood sugar levels. All were measured for body composition and asked about their eating, exercise, and family health history.
- Key finding: Women with gestational diabetes had thicker fat layers under their skin (21.5 millimeters versus 19.0 millimeters) and more water in their bodies (34.6% versus 31.9%), even though they started pregnancy at similar weights. They were also more likely to have family members with obesity or diabetes.
- What it means for you: If you develop gestational diabetes during pregnancy, your body may store fat differently than other pregnant women. The good news: the study shows that women with gestational diabetes often make positive changes to their diet and learn more about nutrition after diagnosis. However, this is one study of 80 women, so talk to your doctor about what’s best for your individual situation.
The Research Details
This was a cross-sectional observational study, which means researchers took a snapshot in time of two groups of pregnant women and compared them. They didn’t follow women over time or randomly assign them to different treatments. Instead, they measured 30 women who already had gestational diabetes and 50 women with normal blood sugar, then looked at the differences between the groups.
The researchers used several methods to measure body composition. They used bioelectrical impedance analysis, a painless test that sends a tiny electrical signal through your body to measure how much is fat, muscle, and water. They also measured skinfold thickness by pinching the skin at specific spots and measuring how thick the fat layer underneath was. Women answered detailed questionnaires about what they ate, how much they exercised, what supplements they took, and their family health history.
The researchers used statistical tests designed for this type of data to figure out which differences between the groups were real and not just due to chance.
This research approach is useful because it shows real-world patterns in actual pregnant women rather than testing something artificial in a lab. By comparing women who already have gestational diabetes to those who don’t, researchers can identify what’s different about their bodies and behaviors. However, because this is a snapshot rather than following women over time, we can’t be completely sure whether the body composition differences caused the gestational diabetes or resulted from it.
This study has some strengths: it measured body composition using two different methods, included detailed questionnaires, and compared two similar groups of pregnant women. However, there are limitations to consider. The sample size is relatively small (80 women), which means the results might not apply to all pregnant women everywhere. The study was done in Poland, so results might differ in other countries with different populations. Also, because women with gestational diabetes knew they had the condition, they may have changed their behavior before being studied, which could affect the results. The study is observational, not experimental, so we can’t prove that one thing caused another.
What the Results Show
Women with gestational diabetes showed measurable differences in how their bodies stored fat and water. Their skinfold thickness (a measure of fat under the skin) was significantly thicker at 21.5 millimeters compared to 19.0 millimeters in women without gestational diabetes. This difference was statistically significant, meaning it wasn’t likely due to chance. Additionally, women with gestational diabetes had higher total body water at 34.6% of their body weight compared to 31.9% in the control group.
Interestingly, these body composition differences existed even though both groups had similar pre-pregnancy body mass index (BMI), a standard measure of weight relative to height. This suggests that gestational diabetes is associated with a different pattern of how the body distributes fat and water, not just overall weight gain.
Family history played a notable role. Women with gestational diabetes were significantly more likely to have a family history of obesity (63% versus 38%) and diabetes (53% versus 28%). This suggests that genetic factors may contribute to gestational diabetes risk.
Women with gestational diabetes showed strong behavioral responses to their diagnosis. A striking 77% of women with gestational diabetes reported following a prescribed diet compared to 0% in the control group. Similarly, 93% of women with gestational diabetes demonstrated greater nutritional knowledge compared to just 4% of controls. These findings likely reflect that women with gestational diabetes received dietary counseling and education after their diagnosis.
Supplement use was common in both groups and similar between them, suggesting that pregnant women in general tend to take vitamins and minerals during pregnancy regardless of gestational diabetes status. Physical activity levels were notably low in both groups, indicating that reduced exercise during pregnancy is common and not unique to women with gestational diabetes. Environmental exposures and other lifestyle factors were comparable between groups, suggesting that gestational diabetes is not strongly associated with differences in these areas.
This study adds to existing research showing that gestational diabetes involves changes in body composition beyond simple weight gain. Previous research has suggested that body fat distribution matters for metabolic health, and this study provides real-world evidence that women with gestational diabetes have different patterns of fat storage. The finding that family history is important aligns with other studies showing that genetics play a role in gestational diabetes risk. The strong dietary changes observed in women with gestational diabetes reflect current clinical practice, where women receive intensive nutritional counseling after diagnosis.
This study has several important limitations. First, the sample size of 80 women is relatively small, which means results might not apply to all pregnant women. Second, the study was done in Poland, so findings may differ in other countries with different populations and healthcare systems. Third, because this is a cross-sectional study (a snapshot in time), we cannot determine whether the body composition differences caused gestational diabetes or resulted from it. Fourth, women with gestational diabetes knew about their diagnosis before being studied, so they may have already changed their diet and behavior, making it hard to know what their natural patterns would have been. Finally, the study relied on self-reported information about diet and exercise, which can be less accurate than direct measurement.
The Bottom Line
If you are pregnant or planning pregnancy, maintain a healthy pre-pregnancy weight and stay as physically active as your doctor recommends. If you develop gestational diabetes, follow the dietary recommendations your healthcare provider gives you, as the study shows this can be effective. Moderate confidence: these findings suggest that body composition monitoring and family history assessment may be useful for identifying pregnancy diabetes risk, but individual medical advice from your doctor is essential.
This research is most relevant for pregnant women, especially those with family histories of obesity or diabetes, as they may have higher gestational diabetes risk. Healthcare providers caring for pregnant women should consider family history when assessing gestational diabetes risk. Women who have had gestational diabetes in previous pregnancies should be aware that body composition changes may persist. This research is less directly applicable to non-pregnant women or men, though family history of metabolic disease remains important for everyone’s health.
If you develop gestational diabetes and make dietary changes, blood sugar improvements can occur within days to weeks. However, changes in body composition (fat and water distribution) typically take weeks to months to become noticeable. Most benefits from dietary adherence appear during the remainder of pregnancy and postpartum period. Long-term health benefits may take months to years to fully develop.
Frequently Asked Questions
What is gestational diabetes and how does it affect your body during pregnancy?
Gestational diabetes is high blood sugar that develops during pregnancy in women who didn’t have diabetes before. A 2026 study of 80 pregnant women found it’s associated with thicker fat layers under the skin and more water in the body, even at similar pre-pregnancy weights. It requires dietary changes and monitoring but usually goes away after pregnancy.
Can family history increase your risk of gestational diabetes?
Yes, family history significantly increases risk. Research from 80 pregnant women showed 63% of those with gestational diabetes had a family history of obesity versus 38% without gestational diabetes, and 53% had family diabetes history versus 28% of controls. If relatives have obesity or diabetes, discuss screening with your doctor.
What dietary changes help manage gestational diabetes during pregnancy?
A 2026 study found that 77% of pregnant women with gestational diabetes followed prescribed diets after diagnosis, and 93% increased their nutritional knowledge. Work with your healthcare provider to create a meal plan that controls carbohydrates and maintains steady blood sugar throughout the day.
Does gestational diabetes mean you’ll have type 2 diabetes later?
Gestational diabetes increases future type 2 diabetes risk, but it doesn’t guarantee it. The 2026 study showed family history matters: women with gestational diabetes were more likely to have relatives with diabetes. Maintaining healthy weight, diet, and exercise after pregnancy can reduce your long-term risk significantly.
How quickly can you see improvements from dietary changes with gestational diabetes?
Blood sugar improvements can occur within days to weeks of dietary changes. A 2026 study showed pregnant women with gestational diabetes made strong dietary commitments after diagnosis. However, changes in body composition typically take weeks to months, and full health benefits may take months to years to develop.
Want to Apply This Research?
- Track daily dietary adherence by logging meals and comparing to your prescribed gestational diabetes diet plan. Measure progress by recording weekly weight and, if possible, waist circumference measurements. Monitor blood sugar readings as directed by your healthcare provider.
- Use the app to set a specific dietary goal, such as eating three balanced meals with controlled carbohydrates daily. Create reminders for meal times and log what you eat to build awareness of your nutrition patterns. Set a realistic physical activity goal, such as a 10-minute walk after meals, and track completion daily.
- Establish a weekly check-in routine where you review your dietary adherence percentage and physical activity minutes. Track trends in blood sugar readings if you’re monitoring at home. Monitor how you feel and any changes in energy levels. Share your app data with your healthcare provider at prenatal appointments to discuss progress and adjust recommendations as needed.
This article summarizes research findings but is not medical advice. Gestational diabetes requires individualized medical care from your healthcare provider. If you are pregnant or planning pregnancy, especially with a family history of diabetes or obesity, discuss screening and prevention strategies with your doctor. Do not make changes to diet, exercise, or supplementation during pregnancy without consulting your healthcare provider. This study is observational and cannot prove cause-and-effect relationships. Results from 80 Polish women may not apply to all populations. Always follow your doctor’s recommendations for managing gestational diabetes and prenatal care.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.