For example, following a very low-carb diet for a long time may disrupt hormones in some women. Eating too few carbs has been associated with disruptions to the menstrual cycle, fertility problems and poor sleep quality. It's also been linked to poor bone health, anxiety and depression. Some women even report weight loss resistance or weight gain.
This article explores how low-carb diets may affect women's hormones.
Low-Carb and Low-Calorie Diets May Affect Women's Adrenals
Your hormones are regulated by three major glands:
- Hypothalamus: located in the brain.
- Pituitary: located in the brain.
- Adrenals: located at the top of the kidneys.
The HPA axis is responsible for regulating your stress levels, mood, emotions, digestion, immune system, sex drive, metabolism, energy levels and more.
The glands are sensitive to things like calorie intake, stress and exercise levels.
Long-term stress can cause you to overproduce the hormones cortisol and norepinephrine, creating an imbalance that increases pressure on the hypothalamus, pituitary and adrenal glands (2).
This ongoing pressure may eventually lead to HPA axis dysfunction, sometimes controversially referred to as “adrenal fatigue" (3).
Symptoms include fatigue, a weakened immune system and greater risk of long-term health problems such as hypothyroidism, inflammation, diabetes and mood disorders.
Many sources suggest that a diet too low in calories or carbs can also act as a stressor, causing HPA dysfunction.
Bottom Line: Eating too few carbs or calories and experiencing chronic stress may disrupt the HPA axis, causing hormonal problems.
A Low-Carb Diet May Cause Irregular Menstrual Cycles or Amenorrhea in Some Women
If you don't eat enough carbs, you may experience irregular menstrual cycles or amenorrhea.
Amenorrhea is defined as a woman's menstrual cycle being absent for 3 months or more.
The most common cause of amenorrhea is hypothalamic amenorrhea, caused by too few calories, too few carbs, weight loss, stress or too much exercise (6).
Amenorrhea occurs due to the drop in levels of many different hormones, such as gonadotropin-releasing hormone (GnRH), which starts the menstrual cycle (7).
These changes can slow some functions in the hypothalamus, the region of the brain responsible for hormone release.
Low levels of leptin, a hormone produced by fat cells, is another potential cause of amenorrhea and irregular menstruation. Evidence suggests that women need a certain level of leptin to maintain normal menstrual function (9, 10).
If your carb or calorie consumption is too low, it can suppress your leptin levels and interfere with leptin's ability to regulate your reproductive hormones. This is particularly true for underweight or lean women on a low-carb diet.
However, evidence on amenorrhea on low-carb diets is scarce. Studies that report amenorrhea as a side effect were usually only done in women following a predominately low-carb diet for a long period of time (11).
Bottom Line: Following a very low-carb (ketogenic) diet over a long period of time may cause irregular menstrual cycles or amenorrhea.
Carbs Can be Beneficial for Thyroid Function
Your thyroid gland produces two hormones: thyroxine (T4) and triiodothyronine (T3).
These two hormones are necessary for a wide range of bodily functions.
These include breathing, heart rate, the nervous system, body weight, temperature control, cholesterol levels and the menstrual cycle.
Reverse T3 is a hormone that blocks the action of T3. Some studies have shown that ketogenic diets reduce T3 levels.
One study found that T3 levels dropped by 47 percent over 2 weeks in people consuming a no-carb diet. In contrast, people consuming the same calories but at least 50 grams of carbs daily experienced no changes in T3 levels (14).
Low T3 and high rT3 levels can slow your metabolism, resulting in symptoms such as weight gain, fatigue, lack of concentration, low mood and more.
One study found that, after 1 year, a diet consisting of moderate carbs (46 percent of total energy intake) had more positive effects on mood than a long-term diet of very low carbs (4 percent of total energy intake) in overweight and obese adults (15).
Bottom Line: Very low-carb diets may cause a drop in thyroid function in some people. This may result in fatigue, weight gain and low mood.
Low-Carb Diets May Affect Fertility
The amount and type of carbs consumed are associated with women's fertility levels.
For example, consuming both too many and too few carbs has been associated with reduced fertility (16).
Following a very low-carb diet for an extended period of time can disrupt hormones, causing amenorrhea or irregular menstrual cycles. This can lower fertility and make it harder for a woman to get pregnant (10, 17, 18, 19).
Bottom Line: Some evidence suggests that following a very low-carb diet for a long period of time can affect menstruation and fertility in women.
How Many Carbs Should You Eat?
The optimal amount of dietary carbs varies for each individual.
Many experts in the field recommend that you consume 15–30 percent of your total calories as carbs.
For most women, this usually equates to around 75–150 grams daily, although some may find a higher or lower carb intake to be more beneficial.
A Moderate Carb Intake May Be Better for Some Women
Certain women may do better consuming a moderate amount of carbs or around 100–150 grams daily. This includes women who:
- Are very active and struggle to recover after training.
- Have an underactive thyroid, despite taking medication (14).
- Struggle to lose weight or start gaining weight, even on a low-carb diet.
- Have stopped menstruating or are having an irregular cycle.
- Have been on a very low-carb diet for an extended period of time.
- Are pregnant or breastfeeding.
For these women, benefits of a moderate-carb diet may include weight loss, better mood and energy levels, normal menstrual function and better sleep.
Other women, such as athletes or those trying to gain weight, may find a daily carb intake of more than 150 grams appropriate.
Bottom Line: A moderate carb intake may benefit some women, including those who are very active or have menstrual problems.
A Low Carb Intake May Be Better for Others
Certain women may do better sticking to a low-carb diet that is under 100 grams per day. This includes women who:
- Are overweight or obese.
- Are very sedentary.
- Have epilepsy (20).
- Have polycystic ovarian syndrome (PCOS), fibroids or endometriosis (21).
- Experience yeast overgrowth.
- Are diagnosed with type 1 or type 2 diabetes (22).
- Have a neurodegenerative disease such as Alzheimer's or Parkinson's (23).
- Have certain forms of cancer (23).
Here is more info about how many carbs you should eat.
Bottom Line: A lower carb intake may benefit women with obesity, epilepsy, diabetes, polycystic ovarian syndrome (PCOS) and other conditions.
Take Home Message
Evidence suggests that women's hormones are sensitive to energy availability, meaning that too few calories or carbs can cause imbalances.
Such imbalances can have very serious consequences, including impaired fertility, low mood and even weight gain.
However, most evidence suggests these effects are generally seen only in women on a long-term, very low-carb diet (under 50 grams per day).
Everyone is different and the optimal carb intake varies greatly between individuals. There is no one-size-fits-all solution in nutrition.
Some people function best on a very low-carb diet, while others function best on a moderate- to high-carb diet.
To figure out what works best for you, you should experiment and adjust your carb intake depending on how you look, feel and perform.
This article was reposted from our media associate Authority Nutrition.
YOU MIGHT ALSO LIKE
By Gudrun Heise
Just as scientists are scoring successes in coronavirus research, new problems are on their way. Fall is with us and winter is around the corner, so the season for colds and flu has begun — joining COVID-19.
Influenza Vaccination<p>A flu vaccination may thus be able to narrow down the diagnostic options when flu-like symptoms occur, but whether such a vaccination also has an influence on the behavior of the dangerous new virus is — like so much else — not clear. "It is conceivable that there is an indirect effect. But it is, I believe, a matter of speculation whether it has an immunological effect in the narrower sense," says Krause.</p><p>Every winter, doctors' waiting rooms are full of people who are coughing and sniffing but who mostly turn out to have only a severe respiratory infection. According to current knowledge, the virus that causes COVID-19, SARS-CoV-2, is also likely to be subject to seasonal fluctuations. </p><p>In winter, cold viruses, at least, flourish because cold and dry air offers ideal conditions for their spread. In addition, it becomes more difficult to air rooms regularly and intensively — an important further measure to counteract the coronavirus and contain to some extent the danger posed by aerosols.</p><p>According to the <a href="https://www.rki.de/DE/Home/homepage_node.html" target="_blank">Robert Koch Institute, Germany's public health agency</a>, between 5% and 20% of people in Germany become infected with flu viruses every year. These viruses are also dangerous and can be fatal. The flu vaccination must be adapted to the influenza viruses every year, because they mutate. But at least there is a vaccination.</p><p>Most experts agree that there is unlikely to be a vaccine against the coronavirus by the time the next wave of influenza comes around. And even if a vaccine were to be approved, many unknowns remain.</p>
COVID-19 and Flu Simultaneously<p>For example, there is a lack of practical experience in dealing simultaneously with SARS-CoV-2 and influenza. It is possible to speculate that having influenza could facilitate the entry of the coronavirus into the human body. "The general weakening of the immune system during an influenza infection could increase the susceptibility of a patient to a SARS-CoV-2 infection," Krause says.</p><p>However, it is uncertain how dangerous this double infection could ultimately be and what can be done about it. Krause is of the opinion that we must arm ourselves against all three diseases — colds, flu and COVID-19. If we have a cold, bed rest, hot tea and cough medicine usually help. We can get vaccinated against flu. But how do we deal with COVID-19?</p><p><span></span>Probably people can only hope that if they get the illness, they will have a mild form with as few after-effects as possible. Here, it will certainly help to stick to suggested rules on hygiene to reduce or prevent our exposure to the virus. In an interview with DW, Bonn-based virology professor Hendrik Streeck made it clear that COVID-19 usually takes a more severe course when there is a high viral load at infection.</p>
Hygiene, Hygiene, Hygiene<p>The same hygiene measures with which we are trying to get at least some kind of grip on COVID-19 also apply to influenza. The less we come into contact with viruses, the greater the chance that we will be spared an infection or that it will be mild.</p><p>These measures include general hygiene precautions such as frequent hand washing and the wearing of protective face masks. "The various hygienic measures against COVID-19 will also reduce the spread of influenza," says Krause. "Possibly, further connections of a more immunological nature will be discovered."</p><p>Let us hope that is the case, because the flu season hasn't even started.</p>
- Fauci Warns Bad Second Wave of Coronavirus Could Hit U.S. ... ›
- U.S. Coronavirus Death Toll Tops 170,000 Ahead of Flu Season ... ›
- COVID-19 Makes Getting a Flu Shot More Important Than Ever ... ›
EcoWatch Daily Newsletter
Rising temperatures in the air and the water surrounding Greenland are melting its massive ice sheet at a faster rate than anytime in the last 12 millennia, according to a new study published Wednesday in the journal Nature.
- Greenland and Antarctica Already Melting at 'Worst-Case-Scenario ... ›
- Warmer Current Is Carving Away Greenland Ice Sheet From Below ... ›
- Greenland's Ice Sheet Is Melting at Rate That Surpasses Scientists ... ›
- Greenland's Ice Sheet Has Reached 'Point of No Return' - EcoWatch ›
- Record Shrinking of Greenland's Ice Sheet Raises Sea Levels ... ›
- Greenland Ice Sheet Melt Creates Huge Waterfalls, Increasing ... ›
A grim new assessment of the world's flora and fungi has found that two-fifths of its species are at risk of extinction as humans encroach on the natural world, as The Guardian reported. That puts the number of species at risk near 140,000.
- Climate Crisis Could Cause a Third of Plant and Animal Species to ... ›
- World Leaders Urged to 'Act Now' to Save Biodiversity - EcoWatch ›
- Bumblebees Face Extinction From the Climate Crisis - EcoWatch ›
- Plant Extinction Is Happening 500x Faster Than Before the Industrial ... ›
As human activity transforms the atmosphere, flowers are changing their colors.
- The Best Plants to Attract Pollinators, by Region - EcoWatch ›
- Corals Turn Bright Neon in Last-Ditch Effort to Survive - EcoWatch ›
- Hummingbirds Live in a More Colorful World, Study Confirms ... ›
By Sharon Zhang
Back in March, when the pandemic had just planted its roots in the U.S., President Donald Trump directed the Environmental Protection Agency (EPA) to do something devastating: The agency was to indefinitely and cruelly suspend environmental rule enforcement. The EPA complied, and for just under half a year, it provided over 3,000 waivers that granted facilities clemency from state-level environmental rule compliance.