In the following sections, we’ll outline complementary approaches that may help lose weight. The below strategies are not meant to replace your standard medical treatment. Make sure to consult with your doctor before making any significant changes to your day-to-day routine. Correct Sleep Schedule
Research over the past few decades has recognized the importance of circadian biology in obesity . Scientists think that circadian biology may have a massive influence on energy balance and metabolism [ 1 ].
In lab settings, mice who ate at the wrong time (when it’s dark for humans) gained more weight, despite the absence of any significant differences in calorie intake or activity over the course of the experiment. The authors suspect that their metabolism shifted [ 1 ].
According to another theory, a disrupted circadian rhythm may be why shift workers seem to be at an increased risk of obesity [ 2 ]. Quantity of Sleep
Short sleep duration has been associated with weight gain in many studies. A meta-analysis of 30 studies and over 630,000 people associated short sleep duration with a 55% higher incidence of obesity in adults and 89% in children [ 3 , 4 , 5 ].
Poor sleep can increase hunger and cravings and disrupt hunger hormones like ghrelin and leptin [ 6 , 7 ]. Take Care of Your Biological Clock (Circadian Rhythm)
Researchers over the past few decades have recognized the importance of circadian biology in obesity . It turns out that circadian biology may have a massive influence on energy balance and metabolism [ 1 ].
Both shift work and being exposed to bright light at night have been linked to an increased risk of obesity [ 2 , 8 ].
What’s the best way to shirt your biological clock?
Start by going outside in the morning [ 9 , 10 ]. A study in 54 people found that getting exposed to lots of light earlier in the day was associated with a lower BMI [ 4 ].
There are several other ways to improve and shift your circadian rhythm, including: eating earlier in the morning and restricting food at night
getting more sunlight during the day [ 11 , 9 , 12 , 13 ]
avoiding bright light at night and wearing blue blocking glasses at night [ 14 , 15 , 16 ]
going to bed and waking up at the same time [ 17 ]
You can find more information about resetting your circadian rhythm here .
Stress is known to cause weight gain. Stress increases cortisol and dynorphin, both of which cause weight gain [ 18 , 19 , 20 , 21 ].
It also increases glutamate , which increases appetite, while decreases NGF and BDNF , both of which are appetite suppressants [ 22 ].
Additionally, it makes the brain resistant to serotonin , a neurotransmitter that also suppresses appetite. Stress also causes resistance to dopamine , which may cause us to eat more as we’ll need to eat more food for the same rewarding effects [ 23 , 24 , 25 ]. Exercise/Physical Fitness
High-intensity exercise is probably the best strategy to lose weight. In addition to promoting fat burning, the increased norepinephrine production may suppress food intake according to a study in rats [ 26 ].
Being active burns calories and jump-starts metabolism. Some studies suggest it also increases BDNF , which supports mental health and might cause us to eat less [ 27 ].
Exercise also increases endorphins , which activates mu-opioid receptors and also suppresses appetite [ 28 ].
Aerobic exercise (like walking, running, swimming, etc) has also been shown to cause major reductions in belly fat in multiple studies [ 29 , 30 ].
Although the reason is not fully understood, yoga can be a useful tool for weight loss too [ 31 , 32 , 33 ].
Scientists are investigating whether MSH , which is increased by sun exposure and helps people tan, can also decrease appetite [ 34 ].
Vitamin D deficiency is suspected to contribute to obesity in some cases, though more research is needed [ 35 ]. UV is hypothesized to prevent obesity in animals, whether or not they are deficient in vitamin D [ 36 ].In one study, intense light exposure, particularly in the morning, was associated with a lower BMI independent of sleep duration and timing [ 4 ].Specifically, having a majority of the average daily light exposure above 500 lux earlier in the day was associated with a lower BMI [ 4 ].Exposure to at least 45 minutes of morning light (between 6-9 am at 1,300 lux) for 3 weeks in obese women resulted in reduced body fat and appetite. Although encouraging, more research is needed to verify the link between sunlight exposure and weight loss [ 37 ].Increased blue light exposure at night has been associated with obesity and weight gain in both humans and mice [ 38 , 39 ].In a study of 54 healthy adults, there was a 1.28 unit increase in body mass index for every extra hour of bright light in the evening [ 4 ].Light exposure in the evening reduces rapid eye movement (REM) and slow-wave sleep, thus worsening metabolic function [ 40 , 41 ].Even dim light at night may disrupt the circadian clock and increase body weight, as seen in a study in mice [ 39 ].Studies have shown that 35% of the variance in body mass index is caused by light exposure, in particular at night [ 4 ].Prolonging daily light exposure increased obesity in mice by decreasing energy expenditure (through a reduced noradrenergic activation of brown fat tissue) rather than increasing food intake or activity [ 42 ].You can reduce your exposure to blue light by wearing blue-blocking glasses for four hours before going to bed, covering any electronics that emit blue or green light with black tape, and put the blinds down at night if light is coming in. Cold exposure increases metabolism and energy expenditure as the body has to adapt and produce more heat. In a clinical […]