As New Yorkers—and most Northeasterners—can attest, it’s been a steamy summer. If you are sensitive to heat, to the point of heat intolerance, this last leg of summer (through September 22nd) can feel unbearable, and leave you feeling hot, tired, lethargic and low energy.
One of the most important first steps to feeling cooler and increasing overall energy—even if it’s not hot outside—is to hydrate well.
Why hydration matters
Up to 75% of Americans are chronically dehydrated. This matters because, overall, the body is composed of 60% water. The brain and heart are about 73% water; the lungs are 83% water; muscles and kidneys are 79% water; the skin is 64% water; and, your bones are about 31% water. Water comprises from 75% of body weight in babies, to 55% of body weight in the elderly.1
Signs and symptoms of dehydration include increased thirst, headaches, dizziness, light-headedness, fatigue, bright or dark yellow urine, rapid heart rate and confusion. Over time, chronic low-grade dehydration can contribute to:
- Lower blood volume in the body, translating to low energy
- A slower metabolism and weight gain
- Impaired cognitive function, affecting concentration, alertness and short term memory2
- High blood pressure
- Urinary tract infections
- Exercise-related asthma
- Increased sugar cravings
- Joint pain
- Kidney disease
Why you feel overly hot—and bothered
Does the heat make you crazy and miserable when others seem fine or unfazed by it? The following factors can contribute to feeing uncomfortably hot and bothered (and not in a good way!).
Insulin. Sweating at night and/or an inability to tolerate heat may reflect blood sugar dysregulation—and may be a sign of insulin resistance or pre-diabetes.3
Thyroid. An overactive thyroid means that there is too much thyroid hormone in the body and that your metabolism is in overdrive, leaving you wired, anxious, feeling hot and overheated.
Estrogen. Being pregnant; experiencing PMS (pre-menstrual syndrome); or going through perimenopause or menopause are all periods of hormonal transition, when women can have too low, too high or fluctuating levels of estrogen, resulting in increased sweating, hot flashes and feeling constantly hot overall.
Cortisol. When you are anxious or stressed (emotionally, physically or mentally), your body’s stress response sets off an alarm system that signals the adrenal glands (located above your kidneys) to release a surge of hormones, including adrenaline and cortisol. Adrenaline increases your heart rate and raises blood pressure, causing you to feel warm and flushed.
As a stimulant, caffeine (whether in coffee, tea or soda) has a thermogenic effect and naturally raises your body temperature.4 Caffeine also triggers the release of stress hormones, increasing heart rate and blood pressure. Too much caffeine, especially on a hot day, can have your heart racing and leave you feeling wired and overheated.
Unfortunately, alcohol and heat don’t mix. Sipping a cocktail by the pool or Aperol spritzes al fresco may seem like a relaxing way to chill on a hot summer day. But alcohol is a vasodilator: it dilates your blood vessels, enabling body heat and a higher volume of blood to rise to the skin surface; this is why you feel flushed, sweaty and hotter than you already are! The combination of losing fluids through sweat (from the heat) and urine (alcohol is a diuretic) is dehydrating, making it difficult for your body to cool down.
According to Consumer Reports, the following over-the-counter and prescription medications can potentially increase heat sensitivity.5 Some medications constrict the blood vessels, interfering with your ability to sweat (and cool the body), or they may affect the brain’s ability to regulate body temperature. As a result, you may feel less able tolerate heat, increasing the risk of sunstroke and/or dehydration.
–Antidepressants and anti-anxiety meds. Desipramine (Norpramin), imipramine (Tofranil), and other anti-anxiety and antidepressant drugs can increase susceptibility to sunburn and inhibit the body’s ability to sweat.6
–Antihistamines and decongestants. Older types of antihistamines, like Benadryl, and decongestants, like Sudafed, may increase heat sensitivity.
–Antipsychotic drugs. The use of antipsychotics drugs, chlorpromazine (Thorazine), aripiprazole (Abilify), lurasidone (Latuda) and rispiradone (Risperdal/Consta), among others, can inhibit your body’s ability to regulate its own temperature and, in hot, humid weather. A potential side effect is hyperthermia (excessive body temperature).7
–Diuretics (a.k.a., water pills). Often prescribed for those with high blood pressure, diuretics, like hydrochlorothiazide and chlorothiazide (also used for edema, fluid retention), work by removing sodium and extra fluid from the body, a recipe for dehydration, electrolyte imbalance and feeling overheated.8, 9, 10
–Anticholinergics. These drugs block the action of acetylcholine, a neurotransmitter, present at different sites of your central nervous system. Anticholinergics are used to treat an overactive bladder, urinary incontinence and chronic obstructive pulmonary disorder (COPD), certain types of poisoning, symptoms of Parkinson’s Disease, diarrhea, asthma, dizziness and motion sickness.11 Potential side effects include dehydration (dry mouth, decreased saliva), decreased sweating and increased heat sensitivity.
How much water is enough?
Drinking enough water is vital for your body to function optimally. A general guideline: drink half your body weight in ounces. For example, if you’re 150 pounds, aim to drink 75 ounces of water (that’s apx. nine 8-ounce glasses of water) daily. You may need to drink more if you have engaged in vigorous or long-duration exercise, spent hours in the heat, or consumed caffeine or alcohol.
The National Academies of Science Engineering Medicine recommends that women drink 2.7 liters (91 ounces) and men drink 3.7 liters (125 ounces) water daily, sourced from all beverages and foods.
Ideally, drink filtered tap water or water from a glass bottle to minimize exposure to plasticizers, like phthalates and bisphenal-A (BPA).
Experts disagree on whether it’s better to drink cold, warm or room temperature water. Ayurvedic or Traditional Chinese Medicine practitioners advocate drinking warm water because your cells absorb it more easily. In my personal experience, I have found that the body is more receptive to warm or room temperature water. While drinking ice cold water can feel like much-needed cool relief on a hot, humid summer day, it “shocks” my system more, and I find myself unable to drink as much water as I need to properly hydrate.
“Sports” Drinks for hydration
Electrolytes are electrically charged minerals, such as sodium, chloride, magnesium, potassium, calcium, found in blood, urine and sweat. They are vital for proper nerve and muscle function, maintaining your blood’s pH and keeping you hydrated. You lose electrolytes any time you lose fluid; for example, when you sweat or urinate.
Athletes who train intensely, for long duration or in the heat, will lose a lot of fluid (through sweat) and often need to replenish electrolytes. Commercial sports drinks, like Gatorade, have been a go-to remedy for electrolyte replacement and hydration. However, depending on the product, Gatorade can be high in sugar, contain artificial sweeteners (like sucralose) and artificial food colorings that can potentially trigger allergic reactions and increase risk of hyperactivity in children.
If you’ve spent several hours at the beach or outdoors on a hot day, you may want to sip on a DIY electrolyte cocktail (click on link for recipe). Or, if you’ve been training hard, you may want to make your own electrolyte solution using this comprehensive electrolyte packet.
Coconut water does contain electrolytes. But, unless, you are drinking it straight out of a fresh young coconut, I am not a fan of store-bought coconut water, which often contains added sugar and, sometimes, questionable ingredients.
Other “flavored waters”
Nope…flavor-infused waters, packaged in plastic bottles, don’t count. For hydrating refreshment, you can drink these naturally flavorful teas warm or cold.
Hibiscus Tea: Hibiscus is a plant known for its beautiful, colorful blooms. The flower and leaves can be made into a tea or extract. In hot weather, hibiscus tea is refreshing; it has a lip-puckering tart, yet sweet flavor. Though it can be sweetened with raw honey and/or sliced fruit, I prefer drinking it unsweetened. Caffeine-free hibiscus is mineral-rich (calcium, magnesium, iron, phosphorus, potassium, sodium and zinc) and a good source of vitamin C and antioxidants. It is also a natural diuretic. Health benefits associated with drinking hibiscus tea include its ability to potentially lower blood pressure, lower cholesterol, improve immune health, provide relief for urinary tract infections, and raise metabolism, enhancing weight loss.12 As delicious and refreshing as hibiscus tea is, do not drink if you are pregnant (hibiscus can stimulate menstruation or premature labor), taking hormone replacement therapy or oral contraceptives; or if you are taking medication for high blood pressure.13 Hibiscus does interact with some medications, so check with your doctor first.
Rooibos Tea. This distinctly “red” tea is grown mostly in the Western Cape of South Africa. Naturally caffeine-free, rooibos is loaded with antioxidants, including two, in particular—nothofagin and aspalthin—that can help reduce stress hormones, like aldosterone and cortisol. It’s also a good source of minerals, like calcium, potassium, magnesium, iron, sodium and zinc, which gives it an astringent zingy flavor. Click here for my Rooibos Tea recipe.
Mint tea: The mint family, which also includes peppermint and spearmint, belongs to the genus mentha. It’s cooling, refreshing and detoxifying, whether you drink it hot or cold. Fresh mint, which I prefer to use in my tea, is widely accessible—you can find it at the grocery store or farmers’ markets. Simply place fresh mint teas in a teapot or mug, add boiled hot water and steep for 5 to 10 minutes.
Foods that are high in water can contribute to overall hydration. Bonus: they are also ideal fat-loss foods because, in addition to being high in water, they also contain fiber, vitamins, minerals and antioxidants. High water vegetables, especially, are low in calories and sugar, so you can eat unlimited amounts. It’s a win-win.
Some examples of nutrient-dense, high water foods include:
- Cruciferous vegetables: Cauliflower, cabbage, broccoli, kale, bok choy.
- Leafy greens: Lettuces, arugula, romaine, spinach, chard, dandelion greens.
- High water vegetables: Celery, cucumbers, radishes, zucchini, tomatoes, bell peppers. Spicy foods, like chili peppers can make you sweat, helping cool the body.
- High water fruits: Watermelon, strawberries, peaches, grapefruit.
- “Wet” bland starches (eaten plain, no added fat): Potatoes with skin on, especially cold potatoes, and corn.
Check out my recipes below featuring high water foods. Enjoy!
RECIPES: Delicious Late-Summer Recipes
*These recipes feature high-water foods that help cool and energize.
— Broccoli-Collagen Smoothie Bowl with Toasted Pumpkin Seeds
— DIY Electrolyte Cocktail
— Detox Spinach-Pear Smoothie
— Liver Cleanse Smoothie
— Fresh Corn Salad with Cumin-Lime Vinaigrette
— No-Cook Creamy Spinach Soup
— Asian Cucumber Noodle Salad
— Zoodles with Arugula Pesto
1, 2 Nutrition Reviews. 2010 Aug; 68(8): 439-458.
3 Temperature. 2016 Jan-Mar; 3(1): 119–145.
4 American Journal of Clinical Nutrition. 1990 May; 51(5): 759-67.
5 Consumer Reports. Aug. 7, 2018
6 Harvard Health Publishing. July 2017
7 State of NJ, Division of Mental Health & Addiction Services.
8 Consumer Reports. Aug. 7, 2018
9 Harvard Health Publishing. July 2017
10 Medline Plus.
12 Organic Facts
13 Medline Plus