Welcome to part 2. Start here in Part 1 so you understand some of the background of this multifaceted hormone that is giving oxytocin a run for it’s money when it comes to a healthy pregnancy, birth and postpartum.

This is the key take away from this article.

Nonpharmaceutical, noninvasive optical interventions can be used to support blood glucose level management in humans.

To recap - as cited in Part 1 - Wai Man G.C. et al., 2017 shows the correlation between the circadian clock and the immune system. Melatonin also regulates the distribution of immune cells throughout the body. (Lymphocyte proliferation, enhancing phagocytosis and stimulating cytokine production - specialist cells that go to injury sites and reduce infection). Therefore, in pregnancy, melatonin can help suppress various inflammatory complications, including preterm labor, gestational diabetes, and preeclampsia.

Why is Gestational Diabetes So Harmful?

If you truly have GD (more on this soon) you’re likely to have sub-optimal melatonin levels. A decrease in melatonin means more glucose transport to your baby, causing the baby’s growth to accelerate and a ‘big’ baby can complicate labor and birth as well as have health implications for moms such as developing type 2 diabetes, heart disease, high blood pressure, and kidney issues. For labor and birth, suspected big baby means induction of labor or a planned cesarean is more likely to be offered.

How Can I Improve My Glucose Readings and/or Prepare for a GTT (Glucose Tolerance Test).

• Ideally get an A1C from your Doctor in the first trimester - this test has been shown to be 98.4% specific for detecting gestational diabetes. Why wait for a GTT - building a healthy baby begins right from conception (in fact pre-pregnancy is the ideal time to make these adjustments to your diet and lifestyle).

• Of course, you’re going to reduce sugar, introduce more protein, and don’t eat high-sugar foods if you haven’t already done so - not to beat the GTT but for your health and your baby’s. Lily Nichols’ books - Real Food for Gestational Diabetes and Real Food for Pregnancy are must-have resources as so many of the standard recommendations are out of date and not evidence-based. Look out for my upcoming podcast with Lily.

• Get out in bright daylight as often as you can in the days before your GTT. These days we spend about 95% of our time indoors exposed to artificial (blue) light and miss out on so many of the benefits of sunlight (and why so many moms are Vitamin D deficient). Increased exposure to bright sunlight can increase nocturnal melatonin levels which then inhibit insulin secretion from the pancreas. Vitamin D, which is primarily produced in the skin in response to sunlight exposure has also been linked with the development of insulin resistance. A 2019 European study of over 13,000 women and men found that those participants who spent more time in the sun in the 7 days before their blood glucose test had improved glucose functioning. More recently (Stalheim et al., 2023) found a link between seasonality and GDM, with the lowest incidence of GDM when pregnancy started during the summer season. Similar findings were found in Verburg et al., (2016) who also found the highest incidence of GDM when pregnancy started in the coldest months.

• While waiting for your GTT use your favorite sessions from the GentleBirth app - meditation reduces blood sugars (stress increases it).

New Research

There is a growing body of evidence of the safety of melatonin in pregnancy to reduce sugar spikes and improve metabolic health (how the body processes glucose). Some of the studies use red and NIR (near infrared) lights to increase melatonin - no supplements are needed. If you prefer not to take a supplement or live in an area with low sunlight in Winter you can create endogenous melatonin with the use of specific light wavelengths.

Researchers now suggest that sitting in front of an affordable red light LED lamp can reduce incidences of glucose spikes by 5% after meals. Spending 15 mins exposed to specific wavelengths of 670nm reduced blood glucose levels by 27.7%.

What is happening in the body?

When we shine this specific wavelength onto the body it changes the viscosity of the ‘water’ in our mitochondria (mitochondria are the energy powerhouses of every cell). They work more efficiently by processing more glucose and boosting your metabolism (cellular respiration).

Light as Medicine

A 2023 a study by Powner and Jeffrey compared exposure to no light vs red light in a blinded RCT in participants due to have a GTT.

7 days before their GTT participants in the experimental group sat in front of a lamp (shining on their back for placebo control) with a power of 40mW/cm2 - about 4ocm away from the body for 15 minutes about 45 mins before the GTT. Participants in the control group had significantly higher glucose readings which reached statistical significance.

Note: The same authors have shown in a fascinating 2022 study using bees - bees that were exposed to the 670nm wavelength had improved glucose control - but those exposed to blue light wavelengths of 420nm had the opposite effect…it slowed down glucose processing. Guess which kind of light most of us are exposed to every day…and what kind of light we’re exposed to sitting in a hospital waiting room. Similar wavelengths of 507nm has been shown to stop labor contractions…red light supports labor.

In 2024, Powner and Jeffrey published a new RCT - A 15 min exposure to 670 nm light reduced the degree of blood glucose elevation following glucose intake by 27.7%, integrated over 2 h after the glucose challenge. (One exposure maintained normal blood sugars for several days). Maximum glucose spiking was reduced by 7.5%. The authors suggest that using PBM with 670 nm light can be used to reduce blood glucose spikes following meals. This intervention may reduce damaging fluctuations of blood glucose on the body. BUT - this study was done on healthy adults - not adults with diabetes so the authors recommend additional research to prove their hypothesis. PBM is considered safe in pregnancy (just don’t shine it on the bump) and given the known risks of the chronic blue light conditions most of us live in (and also not getting much sunshine) makes it a hack well worth considering.

Why is This Important?

A diagnosis of GD brings with it a ‘high risk’ label and additional monitoring - even when moms have perfect blood sugars with exercise and protein/carb combinations there can still be pressure to induce even if baby is the perfect size. Depending on which country you live in - the range of blood sugars to be diagnosed with GD may differ.

Light is Medicine

This is from the 2023 study from Powner and Jeffrey.

Mitochondria regulate metabolism, but solar light influences its rate. Red light increases mitochondrial membrane potentials and ATP production and may increase glucose demand. Here we show, with a glucose tolerance test, that red light exposure in normal subjects significantly reduces blood sugar levels. A 15 min exposure to 670 nm light, reduced the degree of blood glucose elevation following glucose intake by 27.7%, over 2 h. Maximum glucose spiking was reduced by 5.1%. Decreased blood glucose correlated with increased exhaled end-tidal CO 2 partial pressure at 1 h, indicating the mechanism includes an increased oxidation rate. Consequently, 670 nm light exposure can be used to reduce blood glucose spikes following meals. This may reduce damaging fluctuations of blood glucose on the body, a major risk factor for diabetic complications, offering a safe, non-invasive intervention for glucose management of diabetes at home.

Isn’t this a fascinating topic! What could be the mechanism of action? Deficient Vitamin D levels? Low melatonin? Lack of exposure to sunlight and less physical activity in the winter months? It all starts with damaged mitochondria.

What are your thoughts?

If you’re interested in getting a red lamp for home use stay tuned for an upcoming blog on what to look for.