Recently, a friend asked me for advice on the diet for poly-cystic ovary syndrome (PCOS). I looked into a “new” solution because the traditional approach has been unsuccessful for her over the many years she has had this condition.


The traditional approach for PCOS is to use a “diabetic-type” diet which would consist of a lower carbohydrate, moderate protein, moderate fat intake to control blood sugar levels. But there is actually research into the low-carbohydrate high-fat (LCHF) diet for PCOS that looks quite promising. One of the most interesting things I came across was that the LC diet decreased insulin levels which in turn decreased the testosterone secretions in the ovaries, thereby alleviating the symptoms of excess hair, acne etc. Anyway I digress. here is the entirety of what I found:



PCOS is associated with obesity, insulin resistance and hyperinsulinemia. Low carbohydrate diets are known to combat insulin resistance and aid weight loss.  Research has shown that a low-carbohydrate, ketogenic diet for PCOS can lead to weight loss and improvements in insulin resistance which proves useful for treating PCOS symptoms.


The Research

In one study “The effects of a low-carbohydrate, ketogenic diet on the polycystic ovary syndrome: A pilot study”, subjects were instructed to follow the low carb ketogenic diet for PCOS, consisting of fewer than 20 grams of carbohydrate per day, for a 6-month study period. The diet included unlimited consumption of animal foods (meat, chicken, turkey, other fowl, fish, shellfish), prepared and fresh cheeses (up to 4 and 2 ounces per day, respectively), unlimited eggs, salad vegetables (2 cupfuls per day), and low carbohydrate vegetables (1 cupful per day). Subjects were strongly encouraged to drink at least six 8-ounce glasses of permitted fluids per day, and discouraged to drink caffeine and alcohol. Subjects were also encouraged to take one multivitamin per day and to exercise at least three times per week on their own, although this was not mandatory.


Body weight and blood pressure were measured at each visit. Blood tests were taken at baseline, 10, and 24 weeks after a 12 hour fast. Serum total and free testosterone, and insulin were measured.


This research shows a low carb ketogenic diet for PCOS led to significant reductions in weight, percent free testosterone, LH/FSH ratio, and fasting serum insulin in women with obesity and PCOS over a six-month period.

–       average body weight change was -12%

–       BMI decreased by 4kg/m2

–       Decreased testosterone (-30%)

–       Decreased fasting serum insulin (-53%)

–       Improvement in insulin resistance

–       Decreased triglycerides by -25.8%

–       Increased total cholesterol +5.4%

–       Decreased blood pressure (systolic -6.3mmHg, diastolic -9.6mmHg)


The hyperinsulinemia of PCOS appears to increase androgen secretion from the ovary as well as to decrease circulating sex hormone binding globulin (SHBG). This research study suggests that a low carb ketogenic diet for PCOS may lead to a reversal of these processes.


Another study, “Favourable metabolic effects of a eucaloric lower-carbohydrate diet in women with PCOS”, was designed to determine whether a reduction in dietary carbohydrate (CHO) content affects β-cell responsiveness, serum testosterone concentration and insulin sensitivity in women with PCOS. In a crossover design, 30 women were assigned to either the standard diet or a lower carbohydrate diet (41:19:40, cho:prot:fat) for 8 weeks with a 4 week washout between. The researchers measured β-cell responsiveness, serum testosterone concentration and insulin and glucose levels.


Basically, in women with PCOS, even modest reduction in dietary CHO in the context of a weight-maintaining diet has numerous beneficial effects on the metabolic profile that may lead to a decrease in circulating testosterone (-23%).


What the Diet Entails

The goal is to reduce your intake of carbs, and increase your intake of proteins. You should aim for 20g per day NET carbs. NET carbs means the total carbohydrate of the food item minus the dietary fiber. Your body doesn’t absorb the carbohydrates from fiber. When you avoid sugar and starches, your body can then maintain a regular blood glucose level. If you have PCOS and are diabetic  you may find it necessary to have your insulin medication reduced if you cut out out the sugar and starches.

What you can eat:

–       Meat (Any type but do try to use organic or grass fed meats)

–       Fish (Any type; salmon is a great fatty fish)

–       Eggs (Cook them any way you like; organic is better)

–       Natural fats (like butter but olive oil and coconut oil are the best)

–       Vegetables growing above grounds.

–       Dairy products (For most PCOS sufferers it is recommended to cut back on dairy, but it doesn’t need to be totally removed. In moderation, it should be perfectly fine.)

–       Nuts (Eat in moderation)

–       Berries (Eat in moderation)

–       Feel free to eat fatty foods, but emphasize monounsaturated (e.g. avocado and olive oil) and saturated fats (e.g. animal fats and coconut oil) over foods that contain polyunsaturated ones (e.g. seed oils).

What you can’t eat:

–       Sugar

–       Margarine (Actually has no health benefits and it just tastes yucky)

–       Beer (Contains yeast, so it’s a ‘liquid bread.’)

–       Fruit , except for small amounts of berries (You don’t have to eliminate it completely, but fruit does have natural sugars. Use as a substitute for desserts)

–       bread and other foods with grains (whole grains are very bit as bad as refined grains … don’t be fooled)

–       cereal

–       beans

–       soda (though diet soda is OK, as it is sweetened by aspartame, not sugar)

–       pasta

–       potatoes

–       pizza crust

–       beer

–       cookies

–       bagels

–       candy

–       honey

–       chips derived from grains

–       pretzels

–       popsicles

–       crackers

–       most condiments (High Fructose Corn Syrup [HFCS] is rife in these toppings … beware!)

–       anything else with high amounts of carbs (in general, be very skeptical of anything in the aisles of a supermarket … read labels religiously!)

–       milk


What To Expect


It is recommended to dive right in and eliminate all the bad foods immediately as oppose to a stepwise process. In the beginning stages your body goes through a “detox” period where you may experience symptoms of withdrawals. These include tiredness, dizziness, heart palpitations, tiredness, and irritability. This will only last a few days. Eliminating the bad foods will stop your body’s ability to retain water and will be lost through your kidneys. To avoid dehydration, drink plenty of water!


If you need help putting together a suitable diet plan to help manage your PCOS, get in touch today.