AG1 (formerly Athletic Greens) is a powdered greens supplement designed to be mixed with cold water and taken once daily, ideally first thing in the morning on an empty stomach. The mixing itself is straightforward, but a few details about water temperature, timing, and storage meaningfully affect whether you get the most out of what is in the scoop. Below is a practical walkthrough of how to prepare AG1, when to drink it, what the first days and weeks tend to feel like, and which situations call for extra caution.
How to Mix It Properly
Each serving of AG1 is one level scoop (about 12 grams) stirred or shaken into roughly 150 to 300 milliliters (5 to 10 ounces) of water. The company recommends cold water, and there is a good reason for that beyond taste. AG1 contains several probiotic strains, and probiotics are sensitive to heat. Research on common supplement-grade strains like Bifidobacterium longum shows that exposure to temperatures around 60°C for just 15 minutes can destroy roughly 95% of viable cells.1Wiley Online Library (Biotechnology Research International). Thermostability of Probiotics and Their α-Galactosidases and the Potential for Bean Products That is only about 140°F, well below boiling. Mixing AG1 into hot coffee, tea, or warm water risks killing off the live bacteria before they ever reach your gut. Cold or room-temperature water keeps the probiotics intact.
The powder dissolves reasonably well with vigorous stirring, but most people find shaking it in a closed bottle or using a small whisk produces a smoother result. AG1 ships with a shaker bottle for this reason. If you let the mixed drink sit for more than a few minutes, it tends to settle and thicken, so drinking it promptly after mixing gives you the best texture and prevents the somewhat grassy flavor from intensifying.
One practical note on how much water you use: more water makes the taste milder but the drink larger, while less water concentrates the flavor. If you find the taste off-putting, leaning toward the higher end of the recommended water range and adding a squeeze of citrus (lemon or lime) helps. Some people blend it into a smoothie with fruit, which is fine as long as the liquid base is not hot. Avoid mixing it into anything carbonated, since the fizz tends to create a foamy, unpleasant texture that is hard to drink quickly.
Timing and Whether an Empty Stomach Matters
AG1’s manufacturer suggests taking it first thing in the morning before eating. The reasoning is partly about absorption and partly about habit formation. Many of the water-soluble vitamins in the formula, particularly B vitamins and vitamin C, absorb efficiently in the small intestine when there is not a large meal competing for digestive attention. Research on nutrient absorption shows that the delivery format and stomach contents can shift how quickly vitamins reach peak blood levels, even when the total amount absorbed ends up being similar.2PubMed. Absorption of folic acid from a softgel capsule compared to a standard tablet In practical terms, taking AG1 on an empty stomach means the nutrients hit your bloodstream faster, though you would likely absorb most of them regardless of timing.
That said, some people experience mild nausea or stomach discomfort when they take AG1 without food, especially during the first week. If that happens, having it alongside a light breakfast is a perfectly reasonable alternative. The difference in absorption between a fully empty stomach and one with a small meal is modest enough that comfort should win. The more important thing is consistency: taking it at roughly the same time each day makes it easier to stick with and helps your body adjust to the routine.
If you work out in the morning, taking AG1 before exercise is fine for most people. Moderate dehydration during exercise does not appear to significantly impair gastric emptying or fluid absorption, so the nutrients should still move through your system normally.3PubMed. Effect of hypohydration on gastric emptying and intestinal absorption during exercise However, drinking a concentrated, nutrient-dense liquid right before high-intensity training can cause stomach sloshing and discomfort in some people. If you train hard first thing, consider taking AG1 about 20 to 30 minutes before your session or immediately after.
What to Expect in the First Week or Two
The first few days on AG1 tend to bring one of two experiences. Some people notice a bump in energy and mental clarity within the first couple of days, while others feel mildly bloated or gassy. Neither reaction is unusual, and both tend to settle within a week or so.
The digestive effects come largely from the probiotics and the prebiotic fiber in the formula. If your diet has been relatively low in fiber and fermented foods, introducing billions of colony-forming units of probiotic bacteria can temporarily shift your gut environment in ways that produce gas. This is not a sign that something is wrong. It is a sign that your gut microbiome is adjusting. Drinking plenty of water alongside AG1 and starting with a half scoop for the first few days can ease the transition if you are prone to digestive sensitivity.
The energy boost people report is harder to pin to a single ingredient because AG1 contains over 70 components. Part of it is likely straightforward: if you were mildly deficient in B vitamins, vitamin C, or zinc, correcting that gap can make you feel noticeably better within days. Part of it may come from the adaptogenic herbs in the formula, which deserve their own discussion.
The Adaptogens in the Formula
AG1 includes ashwagandha and rhodiola rosea, two of the most widely studied adaptogenic herbs. Adaptogens are plant-derived compounds thought to help the body manage stress more efficiently, and the research on these two is more developed than for most herbal ingredients in the supplement market. Ashwagandha has been studied for its ability to lower cortisol levels and promote neurotrophic factors involved in brain health, while rhodiola rosea appears to influence monoamine concentrations (the brain chemicals tied to mood and alertness) and modulate stress-response pathways.4Frontiers in Nutrition. Rhodiola rosea, Ginkgo biloba, and Ashwagandha as novel antidepressant supplements: converging monoaminergic, neurotrophic, anti-inflammatory, and brain health pathways in depressive disorders
Adaptogenic effects tend to build gradually rather than hitting like caffeine. Most clinical trials on ashwagandha and rhodiola run for at least four to eight weeks before measuring outcomes, so expecting a dramatic difference on day one is unrealistic. If AG1’s adaptogens are going to make a noticeable difference for you, you are more likely to recognize it as a subtle improvement in stress tolerance and sustained energy over the course of a month, not as an immediate jolt. Some people never perceive a distinct adaptogen effect at all, which does not necessarily mean the compounds are doing nothing; it may just mean the effect is small enough to blend into the background of daily variation.
Storage and Shelf Life
AG1 comes in single-serving travel packs and a larger pouch with a 30-day supply. The travel packs are individually sealed and shelf-stable at room temperature, making them convenient for trips. The larger pouch is a different story. Once opened, AG1 should be stored in a cool, dry place, and the company recommends refrigerating it. This is primarily about the probiotics. Free probiotic bacteria are vulnerable to environmental stresses during storage, and keeping them cool helps preserve their viability until you actually consume them.5PubMed Central. Drying of probiotics to enhance the viability during preparation, storage, food application, and digestion: A review
Humidity is the other enemy. Greens powders are hygroscopic, meaning they absorb moisture from the air. If you live somewhere humid and leave the pouch open on the counter, the powder can clump, degrade, and potentially grow mold. Seal the pouch tightly after each use. If you transferred the powder to a different container, make sure it is airtight. The refrigerator solves both the temperature and humidity problems at once, which is why it is the safest default.
Once mixed with water, AG1 should be consumed within about 20 minutes. The vitamins begin to degrade once they are dissolved, especially vitamin C, which is sensitive to light and oxygen. Mixing a batch the night before and storing it in the fridge overnight is technically possible but not ideal. You lose some potency, and the texture becomes unappealing.
Medication Interactions Worth Knowing About
AG1 contains vitamin K, which is the nutrient most commonly flagged for potential drug interactions. If you take a vitamin K antagonist (warfarin is the most common one), you have probably been told to keep your vitamin K intake consistent. The actual evidence on this interaction is more nuanced than the standard advice suggests. A systematic review of studies on dietary vitamin K and anticoagulant response found conflicting results: some studies showed a negative correlation between vitamin K intake and stable anticoagulation, while others suggested that a minimum daily amount of vitamin K is actually needed for adequate coagulation control. The effect on blood clotting seemed to matter mostly at high intake levels, above roughly 150 micrograms per day.6PubMed Central. Interaction Between Dietary Vitamin K Intake and Anticoagulation by Vitamin K Antagonists: Is It Really True? A Systematic Review
The practical takeaway is that adding AG1 to your routine while on warfarin is not automatically dangerous, but you should not do it without telling your prescriber. The issue is not so much the absolute amount of vitamin K in a serving of AG1 (which is moderate) but the change in your daily baseline. If you have been eating a low-vitamin-K diet and suddenly add a supplement that provides a consistent dose every morning, your INR readings could shift. The safest approach is to start AG1, keep your dose consistent, and get your INR checked a couple of weeks after you begin. Your doctor can adjust your warfarin dose accordingly.
Beyond warfarin, AG1 contains ingredients that can interact with other medications in less dramatic ways. The B vitamins and zinc can compete with certain antibiotics for absorption if taken at the same time. Ashwagandha may theoretically enhance the effects of sedatives or thyroid medications. None of these interactions are considered high-risk for most people, but if you take prescription medication daily, a quick conversation with your pharmacist before starting AG1 is a low-effort way to rule out problems.
Can You Take AG1 With Other Supplements
Many people who buy AG1 are already taking other supplements and want to know what they can safely combine. The most important consideration is avoiding excessive intake of fat-soluble vitamins, specifically vitamins A, D, E, and K. Unlike water-soluble vitamins (where your body excretes the excess fairly easily), fat-soluble vitamins accumulate in tissue, and very high doses over time can cause problems. AG1 contains meaningful amounts of all four. If you are also taking a standalone vitamin D supplement, a multivitamin, or a fish oil that is fortified with vitamin A, add up the total daily intake across all your products and compare it to the tolerable upper intake levels published by health agencies.
Omega-3 fish oil, magnesium, and collagen are the supplements most commonly stacked with AG1, and none of those present a meaningful interaction risk. Creatine is also commonly combined without issue. If you take a separate probiotic, there is no danger in combining it with AG1, though you may be spending money on redundancy, since AG1 already includes several strains at a declared dose of 7.2 billion colony-forming units per serving.
Iron supplements are worth separating by a couple of hours. AG1 contains calcium, and calcium competes with iron for absorption in the gut. If your doctor has prescribed iron for a deficiency, take the iron at a different time of day to avoid blunting its effect.
Third-Party Testing and What It Tells You
AG1 carries NSF Certified for Sport certification, which is one of the more rigorous third-party programs in the supplement industry. NSF’s dietary supplement certification involves testing for unsafe levels of contaminants and verifying that the product contains only the ingredients listed on the label.7Academic Press. NSF International’s role in the dietary supplements and nutraceuticals industries The “Certified for Sport” designation adds testing for substances banned by major athletic organizations, which is why you see AG1 marketed to athletes. This matters more than it might seem. The dietary supplement industry in the United States is not required to prove product quality before going to market, so third-party certification programs fill a gap that regulation leaves open.8PubMed. Quality assessment programs for dietary supplements
What NSF certification does not tell you is whether the doses of individual ingredients in AG1 are high enough to produce the effects those ingredients are studied for. Many of AG1’s herbal and adaptogenic ingredients are included in a proprietary blend, meaning the total weight of the blend is disclosed but the exact amount of each ingredient is not. This is common in the supplement industry and frustrating for people who want to compare doses against clinical trial protocols. For some ingredients like ashwagandha, the effective doses used in research are well-established (typically 300 to 600 milligrams of a standardized extract), but without knowing exactly how much AG1 provides, you cannot confirm you are getting a clinically meaningful amount.
Who Should Skip AG1 or Check With a Doctor First
Pregnant and breastfeeding women should talk to their OB-GYN before starting AG1. The formula contains herbal adaptogens that lack robust safety data in pregnancy, and the vitamin A content, while within normal ranges for a non-pregnant adult, requires more careful management during pregnancy because excess vitamin A is teratogenic.
People with autoimmune conditions should be cautious with ashwagandha, which can stimulate immune activity. If you are on immunosuppressive therapy for a condition like lupus, rheumatoid arthritis, or after an organ transplant, adding an immune-stimulating herb without medical guidance is not a good idea. Similarly, anyone with a thyroid disorder, particularly hyperthyroidism, should know that ashwagandha may influence thyroid hormone levels and could complicate management of the condition.
Children and adolescents are another group where AG1 is not well-suited. The formula is dosed for adults, and some of the vitamin and mineral levels exceed what is recommended for younger age groups. If you want to give your child a greens supplement, look for one specifically formulated for pediatric use with age-appropriate nutrient levels. AG1 is not that product.
Finally, if you have kidney disease or are on dialysis, the potassium, phosphorus, and certain vitamin levels in AG1 could be problematic. People with impaired kidney function need to manage electrolyte and mineral intake carefully, and adding a concentrated multi-nutrient supplement without checking the label against your dietary restrictions is risky. Run the ingredient list past your nephrologist or renal dietitian before adding it to your routine.