They’re sprouting up on store shelves and packed into puddings and pretzels and even jams. According to forecasts from Grand View Research, a firm that tracks the food industry, the market for chia seeds is expected to grow by more than 22 percent per year between 2019 and 2025.

Such is the life cycle of the chia seed — always popping up in one trend or another. The seeds have long been a staple in Latin America, and were even offered to Aztec gods during religious ceremonies, but every generation in America seems to think they’ve discovered them for the first time, said Beth Czerwony, a registered dietitian with the Cleveland Clinic’s Center for Human Nutrition.

During the last 40 years, chia has maintained a fairly constant presence in the public consciousness. They appeared as the furry plant Chia Pets in the late 1970s, and by the ’90s, health food companies started marketing them as a nutritional powerhouse. Over the past decade in particular, the tiny seeds have garnered an outsized reputation: as a purported hack for weight loss, a protein supplement and a staple of the ultra-healthy.

Now, thanks in part to social media, chia seeds are again on many people’s minds. Some TikTok users tout the purported benefits of an “internal shower” — a viral trend that involves drinking a supposedly cleansing sludge of chia seeds, water and lemon to relieve constipation and aid with weight loss. The hashtag #internalshower has been viewed more than 100 million times.

“When it was trendy in the early 2000s, the kids talking about it now might not have even been born,” Ms. Czerwony said. “Everything old comes back.”

We asked nutritionists and doctors if the latest chia craze lives up to its healthy hype.

Are chia seeds really that good for you?

Chia seeds are not a magic conduit to weight loss or a cure for disease, but they are “incredibly healthy as a natural food source,” said Dr. Melinda Ring, an integrative medicine specialist at Northwestern Medicine.

As with anything, though, you have to be careful to not overdo it, said Dr. Lisa Ganjhu, an associate professor at the N.Y.U. Grossman School of Medicine who specializes in gastroenterology. She warned against eating the seeds straight, which can upset digestion. Instead, soak them in water or plant-based milk for several hours until they expand to a gelatinous slime, or add ground chia seeds to baked goods. You can also swirl them into a smoothie, where they can absorb the liquid, or else mix them into a pudding.

If you eat too many chia seeds — say, several pounds in a sitting — you run the risk of bloating, cramping, discomfort and diarrhea, she said.

What are the health benefits of chia seeds?

A serving of chia seeds — roughly two tablespoons — won’t transform your entire diet, or replace the vitamins you should be getting from vegetables. But doctors and dietitians point to a few key health benefits:

They’re high in fatty acids.

Chia seeds contain remarkably high levels of an omega-3 essential fatty acid known as alpha-linolenic acid, or A.L.A. You can only get these acids from your diet, Dr. Ring said, and eating foods that are rich in A.L.A.s can help prevent heart disease. In fact, the seeds are one of the richest plant sources of omega-3 fatty acids; one serving has more than twice the daily amount of A.L.A. recommended by the National Institutes of Health.

They have lots of fibre

Two tablespoons of chia seeds have around ten grams of dietary fiber — more than twice that of an apple. Fiber-rich foods promote gut health by encouraging bowel movements — hence, the thought behind the “internal shower.” But Dr. Ganjhu said she thinks of chia seeds as more of an “internal Brillo pad.”

“It will definitely push things through,” she said.

The fiber in chia seeds can also keep you fuller for longer, especially if you soak the seeds first. The soft outer layer that coats seeds softens up and congeals into a gel-like form, which can further expand in your stomach, Ms. Czerwony said.

They contain antioxidants.

Chia seeds are high in several potential antioxidants, which can help break down free radicals that damage our cells, Ms. Czerwony said. While it is possible to have too many antioxidants, doctors say most people would benefit from more in their diets, because free radicals can build up in the body over time, leading to — among other problems — plaque formations in the heart.

They’re a handy workaround to dietary restrictions.

Ms. Czerwony said she has seen patients use chia seeds, which are gluten-free and vegan, as an egg substitute, using the similar consistency to bake pancakes and breads.

And chia seeds are a good source of protein, although considerably less so than soybeans or quinoa, Dr. Ring said, which makes them an ideal supplement for vegetarian diets, or for anyone looking to lower their meat intake.

“It’s a good trend — it’s healthy,” Ms. Czerwony said. “It’s not going to hurt you.”

An increased interest in maintaining a healthy lifestyle has prompted recent studies on the health benefits of novel functional foods such as chia seeds, acai berries, and apple cider vinegar, all of which have significant nutritional and disease prevention characteristics. Chia seeds, in particular, are often referred to as a “superfood” or functional food. What are chia seeds?

Research interests in chia seeds were prompted by their high content of ?-3 fatty acids, with a potential role in reducing the risks of chronic diseases such as diabetes, cardiovascular disorders, nervous system diseases, and inflammatory diseases. Chia belongs to the Lamiaceae family of oleaginous plants, which originates from Southern and Central America.

Chia seeds are increasingly popular as a gluten-free alternative, and the grain is widely available as whole seed, oil, and flour. Additionally, chia seeds are often incorporated into various food products such as multigrain bread, cereals, and nutrition bars as a result of their nutritional properties.

In terms of their macronutrient content, chia seeds contain carbohydrates (42.12?g/100?g), fat (30.74?g/100?g), dietary fiber (34.4?g/100?g), and protein (16.54/100?g). These seeds also contain antioxidants in significantly higher quantities than many other crops and are high in phenolic compounds, which are known for their antioxidant content.

Protein

The protein content of chia seeds is around 15–24%. The main protein component is globulins, which comprise 52-54% of total storage proteins, as well as albumins, glutelin, and prolamin which make up 17.3%–18.6%, 13.6%, and 17.9% of the protein content of chia seeds, respectively.

Globulins are a rich source of glutamic, aspartic, aromatic, and sulfur amino acids. Overall, these globulins contain essential amino acids including leucine, lysine, histidine, valine, isoleucine, methionine, threonine, phenylalanine, and tryptophan. These amino acids also play a role in metabolic activity.

Glutamic acid is associated with stimulating the central nervous system and athletic endurance. Aspartic acid also contributes to proper nervous system function and the regulation of hormones. Comparably, sulfur-containing amino acids are implicated in the function of tertiary and quaternary structures of proteins. Moreover, chia seeds are also a potential source of bioactive peptides, which can act as protecting agents against oxidative processes.

w-3 and w-6 fatty acids in chia oil lend themselves to skin applications because they can inhibit melanin hyperpigmentation. More specifically, these fatty acids can down-regulate the expression of melanogenesis-related genes that encode key melanogenic proteins. These phenolic compounds also possess antioxidant properties that can mitigate the effect of oxidants that promote cell damage.

Chia seeds also possess cardioprotective effects. For example, w-3 fatty acids can improve heart health, as indicated by previous studies demonstrating that the increased uptake of ALA can decrease the risk of mortality from heart failure.

Another investigation revealed that the key benefits of chia seeds on the cardiovascular system include a good source of w -3 fatty acids, higher fiber, and iron content, as well as better calcium and magnesium profiles as compared to milk. This study also demonstrated the ability of chia seeds to stabilize blood glucose levels in diabetic patients, prevent myocardial infarction and strokes by inhibiting platelet aggregation, and reduce blood pressure.

Conclusion

In summary, chia seeds are an ancient grain whose growing popularity worldwide is driven by its nutritional profile that offers a wealth of functional benefits. In particular, ALA places chia seeds as an excellent source of w-3 fatty acids, which have been associated with many positive physiological functions in human beings.

In addition, chia seeds are a good source of antioxidants that have cardiac, hepatic protective effects, anti-aging, and anti-carcinogenic properties. Chia seeds are also a great source of dietary fiber, which is beneficial for the digestive system and plays a role in the control of the development of diabetes.

On a macromolecular level, chia seeds contain unsaturated fatty acids, gluten-free protein, vitamins, minerals, and phenolic compounds, all of which are essential components of a healthy balanced diet. On a systemic level, chia seeds can have a therapeutic role in diabetes, dyslipidemia, and hypertension, in addition to having an important role in anti-inflammatory and anti-oxidative processes Chia seeds have also been reported to provide antidepressant and analgesic properties, as well as potential supporting roles in vision and immune processes.

(BBC)