Athletic Greens, now commonly known as AG1, is a popular greens powder supplement marketed as a nutritional shortcut for overall wellness, immunity, energy, and digestion. It contains a complex blend of vitamins, minerals, probiotics, prebiotics, and adaptogens derived from whole food sources. While many users report positive experiences, it is not without potential downsides. Understanding the side effects of Athletic Greens and who should be cautious is key to making an informed decision about this supplement.
Common Digestive Side Effects
Perhaps the most frequently reported side effects of AG1 are related to digestive discomfort. As with any significant change to diet or supplement intake, the body can take time to adjust. Potential issues include:
- Bloating and Gas: Many users experience increased gas and bloating, which can be attributed to the high fiber content, prebiotics, and probiotics in the formula. Ingredients like inulin and certain fibers can ferment in the gut, causing gas production, particularly in those with sensitive digestive systems.
- Diarrhea or Loose Stools: The sudden introduction of a high dose of fiber and new probiotic strains can send the gastrointestinal tract into overdrive, leading to loose bowel movements. For most, this subsides as the body adapts, but if it persists, discontinuing use may be necessary.
- Upset Stomach and Nausea: Some users, particularly those with sensitive stomachs, report feeling nauseous or experiencing general stomach upset after taking AG1. This can be due to the sheer concentration of ingredients or a sensitivity to a particular component like stevia.
Allergic Reactions and Ingredient Sensitivities
While rare, allergic reactions to ingredients in AG1 are possible. The powder contains a wide variety of botanicals and extracts, and individuals with existing sensitivities should scrutinize the label. Key ingredients to watch out for include:
- Soy: AG1 contains soy, which is a common allergen. Individuals with a soy allergy should avoid this product.
- Alfalfa: Found in the formula, alfalfa is generally not recommended for people with certain autoimmune conditions, such as lupus, as it may stimulate the immune system.
- Green Tea and Wheatgrass: Some people are sensitive or allergic to green tea extract or wheatgrass, which can cause symptoms ranging from headaches and nausea to more severe allergic responses.
Excessive Nutrient Intake and Potential Toxicity
AG1 contains high doses of many vitamins and minerals. While most excess water-soluble vitamins are simply excreted, large amounts of certain nutrients, especially fat-soluble vitamins (A, D, E), can accumulate over time. This poses a risk for individuals already taking other supplements or multivitamins. For example, high doses of vitamin C can increase the risk of kidney stones in susceptible individuals, and excessive vitamin B6 and B12 intake has been linked to potential temporary neuropathy and acne. The company's use of a proprietary blend also means the exact amounts of many ingredients are not disclosed, making it difficult to assess effective dosage or potential for overconsumption.
Significant Drug Interactions and Health Condition Contraindications
Certain ingredients in AG1 can interact negatively with prescription medications, making it unsafe for some people without consulting a doctor first.
- Blood Thinners: AG1 contains vitamin E and high amounts of vitamin K from green foods, which can have blood-thinning effects and interfere with medications like warfarin.
- Immunosuppressants and Autoimmune Conditions: The presence of alfalfa may cause issues for people with certain autoimmune disorders like lupus.
- Thyroid Medication: High biotin intake can potentially interfere with thyroid lab test results.
- Kidney Disease: The potassium and phosphorus content in AG1 can be dangerous for individuals with end-stage kidney disease.
The Heavy Metal Concern
Another potential risk associated with many greens powders, including AG1, is heavy metal contamination. As plants absorb minerals from the soil, they can also absorb toxic heavy metals like lead and arsenic, even in organic produce. Because greens powders are concentrated, the risk is higher than with whole foods. While Athletic Greens states its product is third-party tested and Certified for Sport by NSF International for banned substances and contaminants, consumer watchdog reports have in the past found trace amounts of lead in some greens powders.
AG1 vs. Live it Up Super Greens: A Comparison
To understand how AG1's potential side effects stack up, a comparison with an alternative can be helpful. Live it Up Super Greens is a common alternative often highlighted for its different formulation and cost.
| Feature | Athletic Greens (AG1) | Live it Up Super Greens | Potential Side Effect Differences |
|---|---|---|---|
| Cost | One of the most expensive greens powders, often priced around $3.30 per serving. | More affordable, priced around $1.33 per serving. | Cost is a significant differentiator, not directly linked to health side effects but a factor in consumer choice. |
| Ingredients | Over 75 ingredients in a proprietary blend, including high doses of some vitamins and adaptogens. | A more transparent list of 20+ organic ingredients. Contains probiotics and digestive enzymes. | AG1's complex blend and high vitamin concentrations increase the risk of over-supplementation or sensitivity reactions. Live it Up's focus on organic ingredients and simpler formula may reduce some risks. |
| Probiotics | Contains 10 billion CFUs (Colony Forming Units) from five probiotic strains, a recent increase that may trigger digestive upset in sensitive users. | Contains 5 billion CFUs, potentially a gentler starting point for those new to probiotics. | The higher CFU count in AG1 could cause more initial GI distress for some individuals adjusting to the new bacterial strains. |
| Allergens | Contains soy and is manufactured in a facility that may process other common allergens. | Non-GMO, sugar-free, caffeine-free, gluten-free, soy-free, and nut-free. | Live it Up offers a safer option for those with soy and other common allergies. |
| Additives/Sweeteners | Uses stevia leaf extract for sweetness. | Uses monk fruit extract for sweetness. | Some people are sensitive to stevia and may experience digestive issues from it. |
| Testing | Certified for Sport by NSF International, confirming third-party testing for banned substances and contaminants. | While not explicitly stated as NSF Certified, its formulation is often praised for its clean approach. | AG1's certification may provide peace of mind regarding purity for some users. |
Conclusion
While Athletic Greens is a popular and nutrient-dense supplement for many healthy adults, it's essential to be aware of the potential side effects before beginning a daily regimen. The most common issues are digestive and often mild, subsiding as the body adjusts. However, the risk of allergic reactions, excessive vitamin intake, and potential interactions with certain medications or chronic conditions means it is not suitable for everyone. It is highly recommended to start with a smaller dose to assess tolerance and to consult with a healthcare professional, especially if you are pregnant, breastfeeding, taking medication, or have an existing health condition. A greens powder should complement a balanced diet, not replace it, and your doctor can help determine if AG1 is the right choice for your individual health needs. For more details on the pros and cons, consider reviewing reports from nutrition experts.
The Healthline AG1 Review can be found here: https://www.healthline.com/nutrition/athletic-greens-review
Key Takeaways
- Digestive Issues: Bloating, gas, and diarrhea are common initial side effects due to high fiber and probiotic content.
- Risk Groups: Pregnant/breastfeeding women, children, and individuals with autoimmune or kidney conditions should avoid AG1.
- Drug Interactions: AG1 can interact with blood thinners and other medications due to high vitamin K content and other ingredients.
- Heavy Metals: Although third-party tested, the risk of heavy metal contamination exists in concentrated greens products.
- Start Slow: To minimize side effects, begin with a half-scoop and gradually increase to the full dose.
- Proprietary Blends: Lack of transparency regarding the quantity of specific ingredients makes it hard to gauge effective dosage.
FAQs
Question: What are the most common side effects of Athletic Greens? Answer: The most common side effects are digestive issues like bloating, gas, upset stomach, and diarrhea, particularly when first starting the supplement.
Question: Can I take Athletic Greens if I am pregnant or breastfeeding? Answer: No, AG1 is not recommended for pregnant or breastfeeding women due to certain ingredients like adaptogens and licorice root, which may not be safe during these periods.
Question: Why does Athletic Greens cause bloating? Answer: AG1 can cause bloating due to its high fiber content and the inclusion of prebiotics like inulin and probiotics. For sensitive guts, this can cause gas as the digestive system adjusts.
Question: Is Athletic Greens safe for people on blood thinners? Answer: No, individuals on blood-thinning medications should avoid AG1. The supplement's high vitamin K content can interfere with these medications.
Question: How can I minimize the digestive side effects when starting AG1? Answer: To minimize side effects, start with a smaller dose, such as a half-scoop, and gradually increase your intake over a few days as your body adapts.
Question: Does Athletic Greens contain heavy metals? Answer: While Athletic Greens is third-party tested, greens powders in general can contain trace amounts of heavy metals absorbed by plants from soil. AG1 holds a certification from NSF International that verifies testing for contaminants.
Question: Who else should not take Athletic Greens? Answer: Besides pregnant and nursing women, those with certain autoimmune conditions (e.g., lupus), children, and people with end-stage kidney disease should avoid AG1. Those on immunosuppressants or thyroid medication should also consult a doctor.
Citations
[ { "title": "AG1 Review: A Dietitian and Health Editor's Take - Healthline", "url": "https://www.healthline.com/nutrition/athletic-greens-review" }, { "title": "AG1 Reviews (2025): A Dietitian's Honest Take on AG1 Next Gen - Live it Up", "url": "https://letsliveitup.com/blogs/supergreens/ag1-review" }, { "title": "Super Greens Powder Side Effects: Bloat and More - Garage Gym Reviews", "url": "https://www.garagegymreviews.com/super-greens-powders-side-effects" }, { "title": "7 Things You Should Know About AG1 Before Buying - Hone Health", "url": "https://honehealth.com/edge/what-to-know-before-buying-ag1/" }, { "title": "AG1 Review | Everything you need to know about AG1! [2025] - Innerbody", "url": "https://www.innerbody.com/athletic-greens-review" } ] }
