Edible seaweed, also known as sea vegetables, are often associated with Asian cuisine. These marine algae have been used since ancient times as traditional food and medicine. Besides being low in calories, seaweed are also a rich
source of essential nutrients. Wakame (
Undaria pinnatifida), a common variety of seaweed and considered one of the healthiest, is loaded with vitamins and minerals, as well as phytonutrients that give it impressive, health-promoting properties.
In a study published in the journal
Nutrition Research, researchers from
The Catholic University of Korea isolated a compound from wakame called fucoidan and examined its anti-diabetic activity. Fucoidan is a carbohydrate that has been found to reduce blood glucose levels in mice. Upon testing its effects on normal and insulin-resistant fat cells, the researchers found that
fucoidan can improve insulin sensitivity and prevent basal lipolysis (breakdown of fat cells) -- a process that occurs excessively during obesity and is
closely associated with insulin resistance.
The anti-diabetic properties of fucoidan from wakame (brown seaweed)
Fucoidan is a sulfated polysaccharide -- an important component of cell walls -- that can be found in many species of algae. Sulfated polysaccharides possess
biological activities that are beneficial to human health. Some of these include antioxidant, anti-viral, anti-tumor, antibacterial and anti-inflammatory activities. According to animal studies, fucoidan has the ability to improve learning and memory impairment, inhibit liver fibrosis (excessive scarring) and stop the proliferation of breast cancer cells.
In their study, the Korean researchers hypothesized that the pharmacological properties of fucoidan may allow it to
act directly on adipocytes (fat cells) and exert anti-diabetic effects. To test this hypothesis, they isolated fucoidan from wakame and treated adipocytes with 10, 50, 100 and 200 micrograms per milliliter (mcg/mL) of fucoidan. Then, they assessed lipid accumulation during adipocyte differentiation.
The researchers reported that fucoidan reduced lipid accumulation and glycerol-3-phosphate dehydrogenase (GDPH) activity -- both of which are dysregulated in
diabetes -- in a dose-dependent manner. Fucoidan also suppressed the expression of peroxisome proliferator-activated receptor
y (PPAR-
y), a major transcription factor associated with adipocyte differentiation. PPAR-
y is the target of Type 2-diabetes drugs like thiazolidinediones which are
used to increase insulin sensitivity.
Fucoidan treatment also stimulated
glucose uptake in normal adipocytes and restored insulin-stimulated glucose uptake in adipocytes with obesity-induced insulin resistance. In the presence of RAW 264.7 macrophages, fucoidan enhanced epinephrine-stimulated lipolysis but reduced basal lipolysis.
Based on these results, the researchers concluded that
fucoidan exerts its anti-diabetic effects by improving insulin-stimulated glucose uptake and inhibiting basal lipolysis in adipocytes without inducing adipogenesis (formation of new adipocytes).
The health benefits of wakame
Wakame is a slightly sweet, silky sea vegetable that's commonly used to make salads or added to miso soup. It is a
great source of essential nutrients, such as vitamins A, C, E, K and B9 (folate), and minerals like sodium, magnesium, manganese and calcium. Wakame is also
rich in iodine, a mineral required for the production of thyroid hormones. Iodine deficiency is a common health problem and is the main cause of hypothyroidism. (Related:
Wakame: an iodine-rich seaweed with impressive fat burning properties.)
Besides micronutrients, wakame also contains plenty of anti-inflammatory and antioxidant compounds. A study published in the
Journal of Applied Phycology even linked the lower incidence and mortality rates of post-menopausal
breast cancer in Japan to the consumption of
wakame. Researchers found that eating wakame helps decrease the concentration of a protein known as uPAR, which
plays a major role in tumor progression and metastasis. uPAR is elevated among post-menopausal women in general.
Although wakame is low in fat, it is also a
great source of omega-3 fatty acids. In fact, wakame contains the
highest amount of omega-3 fatty acids among all vegetarian sources. Omega-3 fatty acids are not only good for the heart, they also help with
mental health problems like depression and ADHD, as well as hormonal issues.
Enjoy the health benefits of wakame by adding it to your daily diet. To avoid any adverse effects, eat only moderate amounts and avoid wakame products that contain a lot of
sodium.
Sources include:
Science.news
Guide.Michelin.com
ScienceDirect.com 1
ScienceDirect.com 2
Link.Springer.com
Journal.LWW.com
WellAndGood.com
FrontiersIn.org
BerkeleyWellness.com
LiveScience.com
Healthline.com