Halle Berry in Bathing Suit is "All Grown Up"

Halle Berry has been wowing fans for years with her unforgettable roles and stunning looks, and did so again yesterday in a swimsuit. "Nisi all grown up #BAPSvibes," she captioned it, in a throwback to her 1997 comedy, in which she played Denise “Nisi,” who wants to open a combo hair salon and restaurant. The 55-year-old is undeniably one of the most gorgeous women ever and never seems to age. The Oscar-winning actress looks incredible and seems to be in the best shape of her life. So how does she do it? Read on to see 5 ways Halle Berry stays in shape and the photos that prove they work—and to get beach-ready yourself, don't miss these essential 30 Best-Ever Celebrity Bathing Suit Photos!

1. She Loves Green Juice

The X-Men star posts about her diet and fitness regime regularly on Instagram and has mentioned in IG stories that she will skip breakfast, but will usually have a green juice. "I normally eat two meals a day," Berry told her Insta story viewers. "I normally skip breakfast and I sort of fast and I do my green drink or I do my bullet coffee," Dr. Steve Hruby, a Doctor of Chiropractic and founder at Kaizen Progressive Wellness explains, "There are many potential benefits of juicing, including weight loss. When you juice, you're taking in all the nutrients from the fruits and vegetables in a concentrated form. This means you're getting all of the antioxidants, phytonutrients, vitamins, and minerals without having to eat the whole fruit or vegetable.

Some other benefits of juicing include:

• Increased energy
• Better digestion
• Clearer skin
• Improved sleep quality

Juicing is a great way to get more nutrients into your diet, and it can be especially helpful if you're trying to lose weight or stay in shape. Just make sure you're using healthy ingredients and avoiding sugary juices or smoothies."

2. Stays Hydrated

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In an interview with Hollywood Life, Berry's trainer Peter Lee Thomas said, "She starts her day with a big glass of water, about 8-12 oz [approx. 236 to 355 ml], usually with a little lemon squeezed into it for flavour. And then directly after that, she will take her amino acids." Brianna Joye, a fitness trainer and founder of BOLD by Brianna Joye explains, "Drinking water helps you live longer & helps your metabolism. It’s crucial for recovery as well. I always tell my clients to aim for at least 2 liters a day! I usually aim for a gallon!"

Lauren Steiner, RD, LDN, MS with LAUREN STEINER NUTRITION adds, "Our bodies are made up of at least 60% water. Water is essential for several metabolic processes in the body, and without it, our cells cannot function properly or optimally. All of the systems in the body are interconnected, so if we are dehydrated, we are going to feel it in more areas than one. For example, the digestive system cannot function properly without water, and overall metabolism cannot be running at its best without proper digestion. If our metabolism becomes sluggish, it is going to be more challenging to lose weight or stay in shape. We should be drinking 2-3 liters per day on average."

3. Doesn't Eat Sugar

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The mother of one has been avoiding sugar for years because she is diabetic. "When I was 19 or 20 years old, right before I was diagnosed with diabetes, I was a complete sugar addict," she told Women's Health. "I started the day with some sort of sugary cereal like Lucky Charms or Cocoa Puffs and I always, always had a candy bar or some sort of hard candy (Jolly Ranchers and Hot Tamales were my go-to's) on me. I was sugared-up all the time." After she learned about her health issue, she stopped eating sugar "cold turkey" and after several weeks of withdrawal symptoms like headaches and mood swings, she no longer craved sugar. Dr. Melina Jampolis MD, internist & physician nutrition specialist and podcast host adds, "Sugar is everywhere. You may not even realize that some of the foods you eat contain added sugar. Here are the top sources:

• 47% from beverages, not including regular milk and 100% juice
• 31% from packaged snacks, candy, and sweets
• 8% from breakfast cereals, breads, and granola bars
• 6% from mixed dishes like sweet and sour chicken or peanut butter and jelly
• 4% from dairy products, including flavored milk and sweetened fruit yogurt
• 2% from salad dressings, sauces, and condiments, including savory ones like ketchup and ranch dressing."

Dave Shelton, Founder & Trainer at My Fitness System adds "diet" sodas aren't great, either: "Artificial sugars are a prime suspect in weight gain and poor health, as they can activate the same pathways in the brain as regular sugar. In fact, they may even be more damaging, as they can trick the body into believing it's getting energy from food, when it's not. This can lead to cravings and overconsumption of other foods."

4. Boxing

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Halle loves to get in the ring! "Boxing is still considered one of the best full-body workouts," Berry wrote in an Instagram post in August 2018. "You'll sculpt every muscle and burn major calories and fat. It dramatically decreases stress levels, develops hand-eye coordination, and builds confidence and discipline. But most importantly... you'll never stop learning....I've been boxing for the past 10 years and regularly for the past three and I love that I always learn a new way to challenge myself and work new muscles." Antoine Hamelin, a kinesiologist, a trainer with 20+ years of experience and CEO of First Step Fitness Trainings says, "Boxing is one of the greatest forms of cardiovascular training that you can do to keep weight off. One of the main reasons for that is that it is anaerobic by nature. Thus, unlike jogging for example, it creates an oxygen debt (that is why you will be working hard at catching your breath in between bouts). So on top of burning a lot of calories because you move both the arms and the legs, your metabolism stays elevated for hours after the exercise is done.It strengthens the body because many ballistic actions are involved in boxing. When you throw a punch, you activate many hip, abdominal and upper body muscles all at once to create a powerful action. Moreover, the intensity at which you produce those movements is always maximal, thus eliciting a muscle growth response.Intense cardiovascular training creates a hormonal response by altering the brain's chemistry. After a boxing session, 'feel-good' hormones like serotonin and dopamine circulate in your body in greater amounts creating a sense of peace and calm that can last for hours."

5. She Changes Up Her Routine

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The actress does everything from yoga to plyometric training and running. Hamelin states, "The body adapts to any physical stress it is presented with. If you lift weights at a certain intensity -- meaning the last few repetitions of a set are challenging -- the body will create new muscle tissue as an adaptation. When you do cardio training, the body adapts as well by increasing the amount of mitochondria -- the organ that extracts oxygen from the blood -- in the muscles. That is why your capacity to run or do any cardiovascular activity increases with time.If the stimulus presented to the body is insufficient, adaptations will not occur. If you stay on the same program for weeks on end, you might top off the capacity of the body to adapt. Hence, it is important to vary both the type of training that you do from time to time -- cardio and weights -- as well as the program itself. For weightlifting, changing every 4-6 weeks is a very good option and will ensure progression; and for cardiovascular training, changing every 2-3 weeks the type of training or the intensity can help you improve greatly over time."