People who want to lose weight often turn to supplements, hoping for an easy solution. However, the effects of most supplements are usually disappointing.
One weight loss supplement that entered the market recently is called spinach extract. It’s claimed to cause weight loss by reducing appetite and cravings.
This article provides a detailed review of spinach extract and its weight loss effects.
Spinach extract is a weight loss supplement made from spinach leaves.
It is also known by the brand name Appethyl, which is owned by the Swedish company Greenleaf Medical AB.
Spinach extract is a green powder that can be mixed with water or smoothies. It’s also sold in other forms, including capsules and snack bars.
The powder consists of concentrated spinach leaf thylakoids, which are microscopic structures found inside the chloroplasts of green plant cells.
The role of the thylakoids is to harvest sunlight — a process known as photosynthesis — which provides plants with the energy they need to produce carbs ().
Thylakoids are composed of about 70% proteins, antioxidants, and chlorophyll, while the other 30% mostly consists of fat ().
Thylakoids are not unique to spinach leaves. In fact, they’re found in the leaves of all green plants — and similar supplements could be made from those plants as well.
Note that other supplements may also be called spinach extract, but this article only refers to the type of thylakoid concentrate found in Appethyl.
SUMMARY Spinach extract — also known as Appethyl — is a weight loss supplement. It contains thylakoids, which consist mostly of proteins, antioxidants, and chlorophyll.
Thylakoids from spinach extract suppress the activity of lipase, an enzyme that digests fat.
This helps delay fat digestion, which increases your levels of appetite-reducing hormones like glucagon-like peptide-1 (GLP-1). It also reduces levels of ghrelin, the hunger hormone (, , , ).
Unlike pharmaceutical weight loss drugs like orlistat, thylakoids cause a temporary delay in fat digestion but don’t prevent it completely.
As a result, spinach extract doesn't have the unpleasant side effects of other lipase-inhibiting drugs, such as fatty stools and stomach cramps ().
It’s not entirely clear what part of the thylakoids is responsible for these effects, but they may be caused by certain proteins or fats called galactolipids (, ).
SUMMARY Spinach extract promotes weight loss by delaying fat digestion, temporarily reducing appetite, and causing you to eat less.
Animal studies show that taking thylakoid-rich spinach extract may reduce body fat and weight (, ).
Studies in overweight adults indicate that adding 3.7–5 grams of spinach extract to a meal reduces appetite for several hours (, , ).
By suppressing appetite, spinach extract may lead to weight loss if taken regularly over a few months.
One study in overweight women found that consuming 5 grams of spinach extract every day as part of a 3-month weight loss program resulted in 43% greater weight loss than a placebo ().
Body mass index (BMI), fat mass, and lean mass decreased as well, but differences across groups were insignificant.
Plus, it should be noted that some of the researchers involved in this study had financial ties to the company that developed the supplement.
Therefore, the findings need to be confirmed by an independent research group.
SUMMARY Studies show that taking spinach extract supplements for a few months may cause weight loss. However, due to a potential conflict of interest, further studies are needed.
Spinach extract may suppress your brain's food reward system, reducing cravings.
When overweight women consumed 5 grams of spinach extract per day, cravings for sweets and chocolate decreased by 95% and 87%, respectively ().
Another study in women suggests that 5 grams of spinach extract reduces cravings for snack foods, including those that are salty, sweet, and fatty. However, no effects on calorie intake at a later buffet were observed ().
The reduction in cravings may be because spinach extract promotes the release of glucagon-like peptide-1 (GLP-1), which acts on your food reward system (, ).
SUMMARY Spinach extract may suppress your brain's food reward system, temporarily reducing cravings. Over time, this contributes to weight loss.
Spinach extract appears to be without serious side effects.
In healthy people, it may temporarily reduce insulin levels and increase blood sugar.
Still, it does not seem to have long-term effects on blood sugar control (, , , ).
Nonetheless, further studies are needed to assess the safety of spinach extract for people with type 2 diabetes.
SUMMARY Spinach extract may reduce insulin levels temporarily. Otherwise, its use appears to be safe and without side effects.
An effective dose of spinach extract is about 4–5 grams when taken with a meal. However, you may need to take it for a few months before you see any effects on your weight ().
Since spinach extract delays fat digestion and reduces appetite for a few hours, it’s of greater use when taken before a meal that contains fat.
You shouldn't expect to see any significant benefits from the supplement alone. As with all weight loss supplements, you also need to make some healthy lifestyle changes.
SUMMARY Spinach extract is of most use when taken with meals that contain fat. An effective dose is 4–5 grams per day.
Evidence suggests that spinach extract may be an effective weight loss supplement.
By delaying fat digestion, it temporarily reduces appetite and cravings. When combined with other lifestyle modifications, this may lead to significant weight loss.
However, many of the scientists studying spinach extract have industry ties. Further studies by independent research groups would strengthen the evidence.