How to Control Your Appetite with Red Light

Did you know that you are not supposed to be hungry all the time? Alternatively, that eating is supposed to make you feel uncomfortable so that you stop eating? People who do red light therapy for 2 hours every morning probably know this. I did not know that for decades! I changed my diet, and added red light to get control of my appetite.

Red light therapy can decrease ghrelin so you feel less hunger. Red light therapy can increase leptin, so you feel full when eating. By decreasing hunger and increasing fullness, red light therapy helps you eat less and lose weight.

Hunger is a biological imperative that says “YOU MUST EAT!” Fullness is another biological imperative that says, “YOU MUST NOT EAT!” The hormones ghrelin and leptin drives these feelings. When ghrelin is high, you are hungrier, and you eat more. When leptin is low, you are not satisfied with food, and you eat more.

Red Light Therapy Decreases Ghrelin, Removing Feelings of Hunger

I have a friend who does not understand what it is like to crave food. I asked her, “You don’t ever feel like food helps relieve stress?” She put her hand on her tummy and said, “I just don’t feel like eating.”

Ghrelin Increases Hunger

Maybe her ghrelin is low. She just doesn’t feel hungry. The rest of us know what it is like to reach for another plate of Chinese food because we just don’t feel full. It just tastes good, and it makes the mouth happy.

Overactive ghrelin production tells the brain “I’m still hungry!” Ghrelin is supposed to recede after we begin eating. When it does not recede, we can eat too much and still want more.

With too much ghrelin, hunger does not go away even when we overeat.

Red Light Therapy Reduces Ghrelin

Red light therapy decreases ghrelin production. That means that red light therapy reduces those calls of “It is time to eat!” In the study we will look at below, two hours of red light therapy every morning significantly decreased the amount of hunger hormone in the blood.

 

Red Light Therapy Increases Leptin, Driving Feelings of Fullness

My friend who doesn’t crave food might also have too much leptin. When she puts her hand on her tummy to say “I just don’t feel like eating,” she is indicating that she feels uncomfortable at the idea of eating food. Healthy people get a shot of leptin while they eat. This is the message that says, “We’re full, stop eating now. If you keep eating, your stomach will hurt.”

Healthy people experience a biological imperative that screams “STOP EATING!” sometime during a meal. Many of us are unfamiliar with this feeling. Louis C.K. says that he doesn’t stop eating when he feels full. He stops eating when he hates himself.

Leptin Increases Fullness

My own experience after 50 years of eating carbs is that a low-fat diet turns off the leptin hormone. A combination of two things helped me get that signal back:

• long sessions of red light therapy
• removing simple carbs from my diet

I had not felt full in decades. My leptin was not telling me: “Please put down the fork.”

I got rid of simple carbs. I started eating veggies, protein, and fat. I soaked up red light every day. I was delighted to find out that I do, indeed, have a fullness alarm.

When we don’t have leptin, even a third serving of Chinese food does not make us feel “full.” Leptin is the hormone that makes the tummy feel stretched, satisfied, and full. If you feel these sensations, you are feeling leptin doing its job. Nutritionists call this feeling “satiety,” which is “satisfaction with food.”

Red Light Therapy Increases Leptin

Red light therapy increases leptin production. It ramps up the imperative “STOP EATING!” that is supposed to happen while you eat. When you are satisfied with food, you do not feel compelled to eat more of it. When you do not feel compelled to eat, you eat less! Feeling full makes me actively dislike eating, so it is easier to eat less.

Red Light Controls the Appetite Better than Sleep

One study found that red light therapy can wipe out sleep-deprivation hunger problems. Have you ever been sleep-deprived and felt unusually hungry? Alternatively, you don’t get enough sleep, and one serving of dinner just does not seem to be enough food? That is not a coincidence.

Our bodies confuse the need for sleep with the need for food. When we need sleep:

• ghrelin goes up, making us hungrier
• leptin goes down, making us unaware we are full of food

In the study, they gave one group a regular night’s sleep, and no light therapy. This group had the baseline ghrelin (“I’m hungry”) and leptin (“I’m full”) hormone levels.

Then they restricted sleep to 5-hours. These subjects got hungrier (they had more ghrelin). They also did not get full (they had less leptin).

Then they gave the sleep-deprived subjects two hours of light therapy upon wakening. The subjects got red, blue, or green light therapy. The red light group had less ghrelin and more leptin than the group that had a good night’s sleep. A subject with 5-hours sleep did better with red light than a subject with 8 hours of sleep but no red light.

You can control your appetite with red light even if you are sleep-deprived.

Table: Sleep Hours and Light Therapy Groups

Controls Had No Light Therapy

The study had two control groups. The first group had 8 hours of sleep, which should be enough to reset and repair the body overnight. The second group had 5-hours of sleep, which we would consider sleep-deprived. These two groups experienced a dim light each morning.

Subjects Had Red, Green, or Blue Light Therapy

The test subjects were all sleep-deprived. They did not nap. Researchers monitored their sleep with body activity trackers. The sleep-deprived had 2 hours of light therapy upon waking. They got red light, blue light, or green light.

Light vs. Sleep: Who Wins?

The study compared five groups as follows:

• 8 hours sleep, no therapy
• 5-hours sleep, no therapy
• 5-hours sleep, red light therapy
• 5-hours sleep, blue light therapy
• 5-hours sleep, green light therapy

We know that sleep deprivation increases ghrelin and decreases leptin. Which group do you think had the lowest hunger hormone levels? Which group do you think had the highest fullness feeling hormones?

If lack of sleep causes ghrelin to go up, the sleep deprived 5-hour groups should have the highest ghrelin.

If lack of sleep causes leptin to go down, the sleep deprived 5-hour groups should have the lowest leptin.

That is not what happened.

Red Light Beat Sleep’s Effect on Hunger

The group with 5-hours of sleep and 2 hours of red light therapy did the best at both suppressing ghrelin and increasing leptin.

The 5-hour sleep + red light therapy had:

• the lowest ghrelin hormone (the least hunger)
• the highest leptin hormone (the most feeling of fullness)

The sleep-deprived red light group did better than:

• the full night sleep group
• the 5-hour sleep group
• the 5-hour sleep and green light group
• the 5-hour sleep and blue light group

If red light can help appetite this much while sleep deprived, imagine what it can do if you have a good night’s sleep.

The group with 5-hours of sleep and 2 hours of red light therapy did the best at both suppressing ghrelin and increasing leptin.

The Red Light Weight Loss Formula

If you wanted to be literal, you could follow the formula in this article.

• Deprive yourself of 3 hours sleep.
• Do 2 hours of RLT in the morning upon waking.

That is silly, because depriving yourself of sleep is still a bad idea.

The bottom line of this study is that 2 hours of red light therapy suppresses hunger and increases feelings of fullness.

Get enough sleep, and do your red light therapy.

All Light Therapies Overcame Sleep Loss

In the study we are looking at in this article, the red light group was short on sleep. Sleep deprivation is going to increase ghrelin and decrease leptin. Despite that hormone handicap, that red light group still had lower ghrelin and higher leptin than the well-rested group.

I wonder what would have happened if one of the groups had enough sleep and 2 hours of red light therapy. Unfortunately, researchers did not test that combination in this study. It only makes sense to hypothesize that a good night’s sleep plus 2 hours of red light therapy would significantly decrease grehlin and increase leptin.

All light therapy groups beat the effects of sleep deprivation on hunger. Despite sleep-deprivation, the blue and green light groups also had better hormone profiles than the well-rested group.

Red Light Reduced Ghrelin (Hunger) by 18.7%

Let’s compare the control group to the red light group.

• The control group had 8 hours sleep, but no light therapy.
• The red light group had 5-hours sleep, and 2 hours of red light therapy.

Here are the ghrelin hormones for both groups (ng/mL is nanograms per milliliter):

• the well rested group had a median 945 ng/mL ghrelin
• the sleep-deprived red light group had 768 ng/mL ghrelin

Compared to the well-rested group, the red light/sleep-deprived group had 177 ng/mL less ghrelin.

The red light group had an 18.7% better ghrelin reading than the well-rested group.

Table: Red Light Group with Poor Rest Had 18.7% Less Ghrelin (Hunger Hormone)

Green Light Reduced Ghrelin by 10.3%

Here are the ghrelin hormones for the well rested and the green light therapy groups:

• the well rested group had a median 945 ng/mL ghrelin
• the sleep-deprived green light group had 847 ng/mL ghrelin

Even though they were sleep-deprived, the green light group’s ghrelin was 98 ng/mL lower than the control group’s. Green light had a 10.3% ghrelin improvement.

Table: Green Light Sleep-Deprived Group Had 10.3% Less Ghrelin (Hunger Hormone)

Blue Light Reduced Ghrelin by 6.4%

Here are the ghrelin hormones for the well rested and blue light therapy groups:

• the well rested group had a median 945 ng/mL ghrelin
• the sleep deprived blue light group had 884 ng/mL ghrelin

The sleep deprived blue light group had 6.4% less ghrelin than the well-rested group with no light therapy.

Table: Blue Light Sleep-Deprived Group Had 6.4% Less Ghrelin (Hunger Hormone)

Red Light Increased Leptin (Fullness) by 19.3%

Here are the leptin hormones for the well rested and the sleep-deprived/red light groups:

• the well rested group had a median 7.9 ng/mL leptin
• the sleep-deprived red light group had 9.8 ng/mL leptin

Compared to the well-rested group, the red light/sleep-deprived group had 1.9 ng/mL more leptin.

The red light group had a 19.3% better leptin reading than the well-rested group.

Table: Red Light Sleep Deprived Group Had 19.3% More Leptin (Hunger Suppression)

Blue Light Increased Leptin (Fullness) by 13.1%

Here are the leptin hormones for the well-rested and the sleep-deprived/blue light groups:

• the well rested group had a median 7.9 ng/mL leptin
• the sleep-deprived blue light group had 9.1 ng/mL leptin

The sleep-deprived blue lighters had a 1.2 ng/mL leptin jump. Blue light had a 13.1% leptin improvement.

Table: Blue Light Sleep Deprived Group Had 13.1% More Leptin (Hunger Suppression)

Green Light Increased Leptin (Fullness) by 5.9%

Here are the leptin hormones for the well rested and the sleep-deprived/green light groups:

• the well rested group had a median 7.9 ng/mL leptin
• the sleep-deprived green light group had 8.4 ng/mL leptin

The green light group had a 0.5 ng/mL leptin improvement. Green light had a 5.9% leptin improvement.

Table: Green Light Sleep Deprived Group Had 5.9% More Lepting (Hunger Suppression)

References

• 904 nm Low-Level Laser Irradiation Decreases Expression of Catabolism-Related Genes in White Adipose Tissue of Wistar Rats: Possible Roles of Laser on Metabolism
• Leptin signaling, adiposity, and energy balance
• Infrared photobiomodulation (PBM) therapy improves glucose metabolism and intracellular insulin pathway in adipose tissue of high-fat fed mice
• Prolonged REM sleep restriction induces metabolic syndrome-related changes: Mediation by pro-inflammatory cytokines
• Insulin resistance is improved in high-fat fed mice by photobiomodulation therapy at 630 nm
• Can low-level laser therapy (LLLT) associated with an aerobic plus resistance training change the cardiometabolic risk in obese women? A placebo-controlled clinical trial
• The potential of phototherapy to reduce body fat, insulin resistance and “metabolic inflexibility” related to obesity in women undergoing weight loss treatment
• [The influence of intravenous laser irradiation of the blood on the dynamics of leptin levels and the quality of life of the patients presenting with rheumatoid arthritis]