Session: Advances in diabetes and pregnancy
Canadian researchers shared some key results from their research on women with gestational diabetes. The use of a real-time (live data) continuous glucose monitor during pregnancy definitely improves outcomes (frequent fingersticks were deemed insufficient to capture both hypoglycemia and post-meal hyper glycemia). CGM use produced 50% less macrosomia and less infant hypoglycemia at birth. For the mom, A1c and time-in-range improved significantly.
UK researchers took a close look at the dietary patterns of mothers with diabetes during pregnancy. Mothers of larger babies tended to consume more unhealthy (processed, high-glycemic-index) carbs than mothers of normal-weight babies. Investigators theorized that the elevated post-meal blood sugars caused by these types of foods was responsible, reinforcing the importance of proper meal planning during pregnancy.
Something the pump companies won’t be happy about: The CONCEPT study showed that pump users actually had 5% less time in range and worse pregnancy outcomes than women taking multiple daily injections. Our thinking is it isn’t the device, it’s the lack of guidance and self-management training provided to far too many pump users.
And what about that magical reappearance of insulin production that occurs during pregnancy in some women with type-1 diabetes? Most women were found to have no detectable c-peptide (a surrogate measure of insulin production by the pancreas) at all times of pregnancy. For women with a detectable c-peptide through the pregnancy, the level was found to be highest at 24 weeks. Women in this group were typically diagnosed as young adults and had type-1 diabetes for only a few years. Then there were women with NO detectable c-peptide for the first 24 weeks of pregnancy, but developed some c-peptide by 34 weeks. 90% Of the babies born to these women were large, and 42% experienced neonatal hypoglycemia, leading to the conclusion the c-peptide was the result of fetal hyperinsulininism (the baby, and not the mom, was producing excess insulin).
Not surprisingly, use of hybrid closed loop systems during pregnancy produced positive results. Tandem’s Control-IQ system stayed in closed-loop mode 97% of the time, increased time in the recommended 63-140 mg/dl range by 18%, and led to significant improvements in the critical post-meal period. Speaking of which, researchers at Harvard University concluded that A1c alone is a poor predictor of birth weight. Glucose variability, especially during the 1st and 2nd trimesters, plays a significant role in large-for-gestational-age development.
Session: Timing Is Everything—The Role of Your Circadian Clock
Scientists at the Hebrew University of Jerusalem explained that circadian rhythm is largely controlled by light. The circadian clock is “reset” by the increased presence of light in the morning, as sensed by the retina. Metabolism is closely linked to the circadian clock. Obesity, in particular, is often related to disruptions in circadian rhythm.
Sleep deprivation has been linked to technology use, consumption of highly processed food and caffeine later in the day, as well as alternating shift work, late food intake and inappropriately timed medication use. The effects of poor sleep quality/quantity include insulin resistance. With intermittent fasting gaining popularity, it is important to know that late eating disrupts the sleep cycle. Analysis of CGM comparing “unrestricted” food intake to 3 meals a day without anything after 6pm showed that later dinner prevents glucose from returning to baseline for overnight and thus decreases overall sleep quality. Glucose levels overnight drive several endocrine hormone responses and can influence glucose and hunger levels in the daytime as well.
It appears that the circadian clock’s start and end times are altered by the content of meals. High-fat diets lead to delay circadian rhythm turn-on. Researchers conducted tests with small/med/large meals at various times of the day. People who consumed a large breakfast lost more weight than those who had a large dinner. Late eaters tended to be overweight/obese, have high insulin resistance, and elevated triglycerides. In fact, eating meals just 3 hours later in the day translated into 3kg less weight loss than someone eating earlier. Other noteworthy effects of meal sizes & timing:
- People with type-2 show lower glucose levels for lunch and dinner and overnight with a larger breakfast compared with the large dinner meal group.
- Breakfast is needed to “prime” (energize) beta cells – priming is done better for the full day if the early AM is a relatively large meal, as this pushes beta cells to produce more insulin from the start of the day
- Those who skipped breakfast had higher glucose rises (peaks) after lunch and dinner compared to those who ate breakfast.
- In terms of meal frequency, those who had three meals per day spent more time in a normal glucose range than those who had six meals. Also, three meals daily produced more weight loss than six meals, even when the calorie content was equal.
Session: Is There an Ideal Time to Exercise?
There was considerable conversation about whether exercising at the same time of day helps to keep exercise consistent. Morning is often considered the ideal time of day to achieve higher levels of exercise performance and consistency. Morning exercise means fewer events and scheduling conflicts, protected time for exercise, simplified planning (especially for those who take mealtime insulin), and less coping/problem solving required. One study showed that elevated levels of cortisol in the morning produce better exercise performance.
The Look AHEAD study compared people who exercised at different times of a day. It showed that people who varied their exercise times engaged in the most overall moderate/vigorous physical activity (the morning exercise group was 2nd most active). Men who exercised in the morning were found to have the best overall fitness level.
On the contrary, post-bariatric surgery patients accumulated the most overall physical activity when exercising at a consistent time of day, specifically the morning. This benefit persisted for a full year of follow-up: exercise was more frequent and of longer duration when performed at a consistent time of day… and morning exercisers fared better than those who exercised later in the day (afternoon exercisers had the worst consistency). A Women’s Health study looked at the association between daily step counts and the timing of physical activity. It found that participants with fewer step counts in the morning had a 26% greater risk of obesity compared to those who had most of their step counts by noon.
Session: Insulin as a Driver of Cancer
Diabetes is associated with an increased risk of many forms of cancer, including pancreatic, uterine, kidney, breast, and endometrial. Insulin is a signal for cells to store fuel and grow. More insulin (as occurs in people who are insulin resistant or taking more than they need) can contribute to tumor growth. In breast cancer studies, black women were twice as likely to be insulin resistant than white women, and were also twice as likely to have poor outcomes with their breast cancer treatment.
Can diet influence cancer outcomes? Apparently, yes. Women with type-2 diabetes and endometrial cancer were found to have decreased levels of circulating insulin and decrease tumor growth when following a ketogenic diet. Colorectal cancer can be affected directly by diet since food comes in direct contact with gastrointestinal cells. A study of adolescents found that consumption of simple sugars (particularly sugar-sweetened beverages) correlated directly with colorectal tumor growth.